Abstract:
There is provided an accessory device for a financial transaction token. The accessory has an onboard power storage device that enables a financial token or card that is in communication with the accessory to operate when the card or token is not in the proximity of a merchant terminal (e.g.; a POS terminal). In one implementation, the onboard power storage device includes a rechargeable battery or capacitor such as a thin-film capacitor that stores sufficient energy to power the accessory&#39;s onboard electronics and/or the electronics of a financial token in communication with the accessory. The accessory may be a subcomponent of another consumer device such as a computing device, communications device, an item of clothing, an item of jewelry, a cell phone, a PDA, an identification card, a money holder, a wallet, a purse, a briefcase, or a personal organizer.

Description:
BACKGROUND 
     Increasingly, consumers have come to rely on debit, credit, and stored value cards as a preferred vehicle to provide payment for transactions. Credit cards provide ready access to funds, offer financial protection superior to cash or checks, support loyalty programs, and allow consumers to take advantage of purchasing opportunities when funds may not be otherwise available. As debit and stored value cards have become increasingly popular, the need for consumers to carry cash or checkbooks is still further reduced. 
     Within the past few years, card associations and issuers have been providing transaction cards that are enhanced with features beyond the typical embossed account number, expiration date, cardholder name, and signature area. “Smart cards,” for example, have now come into popular use, and allow for enhanced security of both debit and credit cards by use of onboard integrated circuits to provide memory and optional microprocessor functionality. Smart cards and other enhanced or memory cards or tokens have found uses from replacements for simple embossed credit/debit cards, toll booth payment, ATM card replacements, and even Subscriber Identity Module (SIM) cards in cellular handsets. 
     Even though smart cards and electronics-enhanced cards have provided improvements over traditional credit cards, they suffer from a number of deficiencies. For example, electronics circuitry on enhanced financial transaction cards must receive externally-provided power to operate. To obtain power from a merchant&#39;s financial or Point-Of-Service (POS) terminal, contact-type smart cards use a physical connector interface; two of such interfaces are defined ISO standards 7810 and 7816. However, many types of cards not in physical contact with a POS terminal or other power source cannot operate, and therefore these cards are necessarily inactive at all other times. Alternatively, some enhanced financial transaction cards obtain power from a terminal-generated RF electromagnetic field by way of an inductor that is part of the card&#39;s circuitry. For example, ISO 14443 defines a popular contactless financial transaction card protocol. However, current contactless cards must be in close proximity to the properly modulated electromagnetic field in order to operate (10 cm in the case of ISO 14443-compliant cards). Due to the intentionally limited power and range of such short range fields, RF-powered cards cannot operate outside of the immediate area of a merchant&#39;s POS terminal, and may not have sufficient power in some cases to provide sophisticated electronic computations or support more power consuming circuitry such as displays. Further, embedded chips of some contactless smart cards often employ cryptographic security algorithms that can be “cracked” or decoded if the time and electrical current required for certain encryption or decryption operations is measured. Several demonstrations of this mode of account compromise have been documented, and thus, the possibility of surreptitious measurement of such parameters without knowledge of the cardholder presents a significant security risk. 
     What is needed then is an accessory device for a financial transaction card or token that provides power to the card or token to support operation of the card or token&#39;s features. What is further needed is an accessory for a financial transaction card or token that has an onboard power source that does not utilize the hazardous chemicals associated with typical power sources such as replaceable or rechargeable batteries. What is also needed is an accessory for a financial transaction card or token that has a power source that is rechargeable and has a form factor that may be easily carried in a pocket or purse. What is further needed is an accessory for a financial transaction token that can allow the token to operate in an environment significantly removed from a POS terminal. What is also needed is an accessory for a financial transaction token that utilizes an onboard power source to provide cryptographic security and protect the token when not in use. What is still further needed is a mobile accessory device that may reprogram a financial transaction card or token to encode a variety of types of account information, thereby allowing for payment flexibility using the financial transaction token. What is also needed is an accessory for a financial transaction token that allows the holder to view information stored in the token without being in proximity to a POS terminal. What is also needed is an accessory for a financial token transaction token that allows the holder to charge an energy storage device on the financial token and view the charge status of the financial tokens&#39; energy source. 
     SUMMARY 
     There is provided an accessory device for a financial transaction token. The accessory has an onboard power storage device that enables a financial token or card that is in communication with the accessory to operate when the card or token is not in the proximity of a merchant terminal (e.g.; a POS terminal). In one implementation, the onboard power storage device includes a rechargeable battery or capacitor such as a thin-film capacitor that stores sufficient energy to power the accessory&#39;s onboard electronics and/or the electronics of a financial token in communication with the accessory. The accessory may be a subcomponent of another consumer device such as a computing device, communications device, an item of clothing, an item of jewelry, a cell phone, a PDA, an identification card, a money holder, a wallet, a purse, a briefcase, or a personal organizer. 
     In one implementation, the accessory includes a housing with a user interface, an integrated processor and storage, an onboard power source, and an interface to a financial token such as a smart card. The user interface optionally has an exposed region that is provided for encoding data including an account to pay for a transaction. The encoding renders data in several alternate or complementary formats, such as light- or laser-scannable bar coding on a display, electromagnetic signals that are transmitted to a merchant receiver, external contact pads for a contact-based pickup, and a magnetic stripe assembly. Using the exposed area, the accessory may complete a transaction with a merchant as a proxy for a financial token that is in communication with the accessory. In one implementation, a financial token that is in communication with the accessory may be reprogrammed by the accessory by accepting inputs from the accessory&#39;s user interface, and a the accessory&#39;s integrated processor transmits data to a processor embedded in the token, which in turn accepts the information and executes software in a processor located within the token to effect the reprogramming. This reprogrammable feature enables the holder of the accessory to secure the token by erasing a display or magnetic stripe or locking the token from unauthorized use. The accessory, when access is granted to a user, may perform calculations such as adding a tip from a predetermined tip percentage, or selecting payment to occur from a variety of different financial accounts. In one implementation, a magnetic stripe assembly in proximity to the token is reprogrammable, so that the token&#39;s embedded processor may select a particular account from input specified in the accessory&#39;s user interface, and provide instructions to reprogram the magnetic stripe. In another implementation, the accessory possesses read/write heads that are capable of reprogramming a financial token as the token is placed within or removed from a retaining cavity within the accessory&#39;s housing. The token&#39;s magnetic stripe may then be swiped through a conventional merchant magnetic stripe reader to initiate payment for a transaction. In yet another implementation, the account information or transaction authorization protocol stored within a financial token&#39;s memory is relayed to an accessory with which it is in communication, and a financial transaction is completed by the accessory in proxy for or in lieu of the token. In another implementation, the token also includes a memory that may optionally be maintained by the onboard power source located within the accessory. 
     In another implementation, an accessory for a financial token provides a charging current to an energy storage device located within the financial token. In this way, a relatively small capacity energy storage element can be recharged by placing the token in communication with the accessory, such as by sliding the token within a slot or cavity within the accessory device. An electrical interface may then proceed to charge the financial token&#39;s energy storage element through current provided by a power source in the accessory, or through relaying charging current that is obtained by the accessory&#39;s external charging interface. In another implementation, the accessory for a financial token possesses a charging circuit that can utilize an onboard energy generation capability to recharge the financial token&#39;s energy storage element and optionally recharge the power source within the accessory. 
     In another implementation, an accessory for a financial transaction card is provided that accepts and retains the card within a protective housing. The card may have a substantially rigid substrate not unlike conventional credit cards and an onboard energy storage device such as a thin-film capacitor. The card includes, in one implementation, a conventional or reprogrammable magnetic stripe assembly that is disposed proximal the substrate. As mentioned previously, the reprogrammable substrate may be configured by a an embedded processor that is commanded through inputs provided to an accessory device with which the card is in communication. In one implementation, the user provides input through a keyboard or an array of contact pads or blister buttons on or integrated into the accessory&#39;s housing Alternately, the user input section may include a biometric input device that scans fingerprints or other biometric data to authenticate the user of the accessory, or may have a pressure-sensitive area for inputting a predetermined access glyph such as by the user dragging a fingertip over a pad to reproduce a symbol that the user has previously identified. In one embodiment, the housing of the accessory retains and protects the card from unauthorized access, such as by preventing physical access to the card through a locking retaining mechanism, and/or by providing shielding against electromagnetic radiation including RF signals. 
     Various features and advantages of the invention can be more fully appreciated with reference to the detailed description and accompanying drawings that follow. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The features, objects, and advantages of embodiments of the disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like elements bear like reference numerals. 
         FIG. 1  depicts a block diagram of an exemplary implementation of an accessory for a financial transaction token including an electrical/data interface; 
         FIG. 2  illustrates possible alternate implementations of the electrical/data interface seen in  FIG. 1 ; 
         FIG. 3  shows an exemplary implementation of a financial token and an accessory for a financial transaction token; 
         FIG. 4  shows a second exemplary implementation of a financial token and an accessory for a financial transaction token; 
         FIGS. 5A-5B  show illustrations of a pendulum and piezoelectric crystal implementation of the charging circuit seen in  FIG. 1 ; 
         FIGS. 6A-6C  show illustrations of a movable mass and piezoelectric crystal implementations of the charging circuit seen in  FIG. 1 ; and 
         FIGS. 7A-7B  illustrates two additional exemplary embodiments for the accessory for a financial transaction token. 
     
    
    
     DETAILED DESCRIPTION 
     A block diagram for an exemplary implementation of an accessory  100  for a financial transaction token is seen  FIG. 1 . The accessory  100  comprises an assembly  102  that houses, supports, and/or integrates the components shown in  FIG. 1 . Those of skill in the relevant arts understand that the assembly  102  may be integrated within a consumer product such as a cell phone or PDA (with embodiments shown in  FIGS. 7A and 7B , respectively), or may comprise a stand-alone assembly. The accessory includes an integrated processor  105 , which those of skill in the relevant arts will appreciate may comprise a microprocessor chip, a microcontroller chip, an ASIC, a digital signal processor (DSP), or a smart card chip. The processor  105  is coupled to a power circuit  115 . The power circuit  115  provides power to the accessory&#39;s electronic components  105 ,  110 , and  130 , and may further include signals indicating charging or connection status. The processor  105  is further coupled to signal busses  120 ,  122 , and  125 , which those of skill in the relevant arts will recognize may be comprised of a plurality of individual dedicated signal circuits, commonly shared signal busses, bidirectional signal circuits, unidirectional signal circuits, or combinations thereof. In one implementation, signal busses  120 ,  122 , and  125  comprise a single commonly shared address/data bus with associated control signals. The integrated processor  105  is coupled to a storage  110  through signal bus  125 . Those of skill in the relevant arts appreciate that the storage  110  may comprise any number of electronic, magnetic, or electromechanical storage devices such as miniature hard drives; SRAM memory; DRAM memory; ROM, PROM, EEPROM, or flash memory; or combinations thereof, and such storage may be included in total or in part upon the same integrated circuit substrate as the processor  105 . The storage  110 , if of volatile type, may have its data values preserved by power provided by the connected power circuit  115 . Data stored in memory  110  may include code or program instructions which, when executed by processor  105 , performs at least part of a command sequence requested by a user through the user interface  130 . 
     An onboard power source  150  is coupled to and energizes the power circuit  115 . Those of skill in the relevant arts will recognize that energy storage devices such as batteries, inductors, capacitors, or combinations thereof may be utilized to implement the power source  150 . In one implementation, power source  150  comprises a thin film capacitor, and may utilize a single dielectric or a multilayer configuration alternating conducting layers and dielectric layers. A number of dielectrics such as polyester, polypropylene, polycarbonate, polystyrene, polyimide, PTFE, PET, and combinations thereof may be utilized in such thin film capacitor implementations. A substantially planar thin film capacitor implementation is beneficial for implementation in the instant accessory device  102 , as the substantially planar form factor may be useful in minimizing the overall size of the accessory&#39;s footprint. In another implementation, power source  150  may be implemented with any number of conventional rechargeable and non-rechargeable batteries such as alkaline batteries, lithium ion batteries, nickel-cadmium batteries, and nickel metal hydride batteries. 
     The power source  150  also provides current to a power line  119  of a financial token interface  145  either directly through a connection  116  coupled to the power circuit  115 , or via output  118  from a voltage regulator  151  which receives power from a coupling  117  to the power source. Those of skill in the relevant arts appreciate that the regulator  151  may be implemented with any number of conventional voltage regulators; for example, but not by way of limitation, such regulators may include alone or in combination: zener diodes, voltage regulator circuits, voltage translators, transformers, voltage dividers, switched power supplies, silicon controlled rectifiers, triacs, potentiometers, and the like. 
     The power source  150  is coupled  157  to a charging circuit  155 . The charging circuit may also be coupled  156  to an external charging interface  158 . Those of skill in the relevant arts will readily recognize that the charging interface  158  may be implemented with electrical contacts to an external circuit, or via an inductor for receiving power via electromagnetic radiation. In one implementation, charging circuit  155  includes one or more photovoltaic cells, coupled to the power source, which produce electricity upon exposure to light. In another implementation, charging circuit  155  further includes one or more piezoelectric crystals electrically connected, via coupling  157 , to the power source  150 , and a movable mass that strikes the piezoelectric crystals as the token  100  is moved. Turning to  FIG. 5A , a piezoelectric charger implementation of the charging circuit  155  is shown. A movable pendulum mass  500  rotates  505 , preferably in a substantially planar motion, about a pinned end  510 . The pendulum mass  500  also has an impact end  525 , that is disposed between and may strike either of two piezoelectric crystals  520 ,  521 . As the crystals  520 ,  521  are electrically coupled  157  to the energy storage device  150 , impacts of the pendulum mass  500  cause pulses of current to be delivered to the energy storage device  150  thus charging the storage device  150 .  FIG. 5B  provides an illustration of the pendulum  500  moving  506  to strike crystal  521 , and likewise, the pendulum mass  500  may move the opposite direction to strike the other crystal  520 . Turning to  FIG. 6A , an alternate mass/piezoelectric implementation of the charging circuit  155  is shown in cross section. A charger housing  600  constrains piezoelectric crystals  520 ,  521  from movement, and crystals  520 ,  521  are electrically coupled  157  to the power source  150 . A movable mass  625  is disposed between the crystals  520 ,  521  within in the charger housing  600 , and the mass is free to move within the spaces defined  610  by the charger housing  600  and the crystals  520 ,  521  as the appliance  100  is moved. Those of skill in the relevant arts understand that charger housing  600  may be implemented by many geometrical shapes that constrain the piezoelectric crystals  520 ,  521  while allowing mass  625  to move in the available space  610 . For example, but not by way of limitation, charger housing  600  may be a cylindrical tube with mass  625  comprising a dense spherically-shaped object such as a metal ball bearing or a dense cylindrical metal slug. Similarly to  FIGS. 5A-B , as the mass  625  strikes crystals  520 ,  521 , pulses of current are produced and charge the power source  150 . An example of the charging circuit of  FIG. 6A  is shown in action in  FIG. 6B . When the accessory  102  containing charging circuit  155  is tilted  620  with respect to ground horizontal, the force of gravity propels mass  625  toward  630  one of the piezoelectric crystals  521 , whereupon the mass  625  strikes the crystal  521  producing a current which is electrically coupled  157  to the power source  150 . Turning to  FIG. 6C , another implementation of a charging circuit  155  is shown with two crystal/mass housings  600 ,  650 . In this illustration, housings  600 ,  650  have been laid out in the charging circuit  155  with central axes oriented orthogonally with respect to each other. Similarly to  FIGS. 5A and 5B , a mass  675  is also movably disposed between two piezoelectric crystal elements  660 ,  661 , that are coupled  157  to the power source  150 , and the mass  675  is constrained by the housing  650 . With this arrangement, rotation of the accessory  100  with respect to horizontal produces alternate mass/crystal strikes between the vertically disposed housing  650  and the horizontally disposed housing  600 . Those of skill in the relevant arts appreciate that any number of crystal/mass/housing assemblies may be included in the charging circuit  155 , and many possible geometric alignments are possible beyond disposal along orthogonal central axes. Those of skill in the relevant arts also appreciate that inertia of the mass  625 ,  675  may be used to cause striking forces as the charging circuit  155  is moved, independently from tilting the device. Therefore, movements such as walking or riding a vehicle may provide sufficient physical displacement to cause charging of the power source  150  to occur. 
     Returning to  FIG. 1 , a user interface  130  is also provided, and is coupled to the power circuit  115  and to the integrated processor  105  via signal bus  122 . In one implementation, the user interface may include one or more conventional displays  135  that may output text, graphics, or a combination. The display  135  may be implemented in such formats as a liquid crystal display, a thin film transistor display, touch-sensitive screen, or organic LED display. The user interface  130  also includes an optional data entry apparatus  140 . In one implementation, the data entry apparatus  140  may include an array of buttons labeled in a manner such as a QWERTY keyboard, a touch pad, a touch screen, or in a more simplistic implementation, a telephone touch pad with alphanumeric key assignments. In one implementation, the buttons in the data entry apparatus  140  may comprise blister buttons commonly known in the art. The user interface  130  may also include an optional on/off button that activates the accessory  100  for selecting desired account access, performing a calculation, or authenticating a user. 
     An external interface  137  is also provided. The external interface  137  enables the accessory  100  to communicate with external devices such as computer terminals, computer networks, or point of sale (POS) terminals. The interface  137  receives data and/or commands for displaying text or graphical information from bus  122 , and receives power from power circuit  115 . The interface  137  may also receive data from an outside source such as a wireless POS terminal, a financial institution, or a personal computer, and relays the data to the integrated processor  105  through data bus  122 . Through user input to the data entry device  140 , a variety of data may be provided to the external interface. In one implementation, the information provided to be output from the interface  137  may comprise health care information, personal identity information, biometric data, music, video data, or a combination thereof, and is considered interchangeable with the term “account data” used herein. 
     Turning to  FIG. 2 , exemplary implementations  200  of the external interface  137  are shown. External interface  137  is depicted with an optional shielding element  137 A, which allows desired electromagnetic, optical, or radiative signals to penetrate while protecting the external interface  137  from physical abuse or damage. The accessory  100  may optionally have areas outside of the external interface  137  shielded from physical abuse or otherwise acceptable forms of electromagnetic radiation. Some of the acceptable signals that are allowed to penetrate the shielding  137 A may include, but are not limited to, signals accompanying a magnetic field, RFID signals, IrDA signals, visible light, invisible light, modulated laser, and/or modulated RF communication signals. By way of example and not by way of limitation, selective shielding element  137 A may comprise a clear plastic shield, conformal coatings, an opaque plastic shield, or a clear thin film, depending on the implementation of external interface  137 . 
     Non-limiting examples of the external interface are shown at reference numeral  200 , and include a magnetic stripe assembly  210 , an antenna and/or transceiver  220 , a display screen  230 , electrical contacts  240 , and a touch screen  250 . The magnetic stripe assembly  210  may comprise, in one implementation  210 A, a reprogrammable magnetic stripe  210 B that accepts data and/or commands from the processor  105  and formats and renders that data into a form on a magnetic stripe that is readable by conventional merchant magnetic stripe-reading POS terminals. In this manner, the processor  105  may program a particular account for use in a transaction as a function of user input selecting the account. Alternatively, the processor  105  may erase the magnetic stripe of the assembly  210 , rendering the card useless in the event of its loss or theft. In the implementation shown  210 A, the magnetic stripe assembly  210 B at least partially slidably moves  210 C into and out of the housing  102  of the accessory  100  (partial view shown), allowing the accessory  100  to conduct a financial transaction at a point of sale terminal that includes a magnetic stripe reader. 
     Continuing with  FIG. 2 , another implementation of the external interface  137  is shown as an antenna and/or transceiver  220 . The antenna  220  may include commonly used loop inductors such as the one shown  220 A, cellular phone antennae, WiFi antennae or in those shown in related ISO standards for RF-readable smart cards. With such an interface, account data may be translated, modulated and transmitted by the accessory in a manner acceptable by an RF contactless merchant Point-Of-Service (POS) terminal, a 802.11 WiFi or WiMax network, or by a cellular or RF communications network. 
     The external interface  137  may also be represented with a display screen  230 . Account data may be rendered in the form of an optically-readable area, such as a one dimensional or two dimensional bar code  230 A. In this manner, merchant POS terminals may optically scan the display area  230  with conventional laser scanners, and obtain account information without the need for expensive contactless RF POS terminals. As the display is electronically reconfigurable with information provided by the processor  105 , the accessory  100  may represent any number of accounts for transaction payment based on the user&#39;s preference and input to the user interface  130 . Also, as a security feature, the display may be blanked or filled with a decorative or entertaining graphic when the user has not provided an optional security access code, pad stroke, or pin number to the user interface  130 . 
     External contacts  240  are yet another alternative implementation of the external interface  137  shown in  FIG. 2 . With the accessory  100  possessing physical contacts such as an array of conductive pads or shapes  240 A, the accessory may be placed in physical contact with a merchant POS terminal, and the external contacts  240  may establish connectivity to the merchant&#39;s financial processing system. The integrated processor  105  may relay account-related information to the merchant POS terminal through the contact interface, thereby allowing the accessory  100  to be utilized with the large number of preexisting merchant POS terminals that accept smart cards. As with the other implementations  210 ,  220 ,  230 , and  250  of the external interface  137 , a combination of techniques may be utilized within the external interface to provide flexibility of use and ease of merchant access to account information. 
     Alternatively, the external interface  137  may comprise a touch screen  250 , wherein text and/or graphics may be displayed, and user input may be accepted by touching selected areas of the screen. For example, but not by way of limitation, in an implementation shown at reference numeral  250 A, a user is prompted to tap on one of a plurality of account descriptors, thereby selecting an account to complete a transaction. Those of skill in the relevant arts also appreciate that tapping the screen may be combined with using pointing devices such as a joystick, direction buttons, or selection wheels. In one embodiment, a user may provide authentication information by touching the display  250  in specified areas to indicate sequences of pin numbers, selected graphical elements, or drag strokes that match a predetermined access criterion stored within the storage  110 . 
     Turning to  FIG. 3 , an implementation of the accessory  100  is shown along with one possible financial token embodiment  300 . The substrate of the financial token  300 , in one implementation, takes the form of a transaction card  300  that is substantially rigid and thin as are conventional credit or debit cards, and possesses substantially similar dimensions as existing credit, debit, stored value, or smart cards. In one implementation, the thickness of card  300  exceeds that of conventional credit, debit, or stored value cards in order to accommodate circuitry, electronics, displays, and/or interface elements. The substrate of the card  300  contains an embedded processor  305  and memory  310 . 
     A front side of the token  300  is shown with an array of buttons  312  and a display  335  for outputting alphanumeric text or graphics, such as an account number and expiration date. An array of physical contacts  350  is shown, which may be utilized in conjunction with a POS terminal, or the electrical/data interface  145 . In the illustrated implementation, the token  300  may be placed within the accessory  100  by, for example, but not by way of limitation, sliding the token  300  into  322  a slot  323  defining a cavity within the accessory housing  102 . The accessory housing  102  retains the token  300  until the user actuates a hardware mechanism such as a latch (not shown) that retains the token  300  within the cavity within the accessory housing  102 . Alternatively, the token  300  could be retained by an electromechanical latch (not shown) coupled to the power source  150  and the integrated processor  105 , wherein the token could be released upon an execution of a command by the processor  105 . For example, but not by way of limitation, if a user entered a valid authorization code into the touch screen interface  250 A, the processor determines the code is valid and provides a command to the electromechanical latch to release the token from the accessory. Alternatively, a drive element (such as those that actuate Compact Disk player disk slots in portable CD players) could eject the card through the slot  323  upon receiving a command to eject the card from the processor  105 . 
     The accessory  100  is shown with a user input mechanism comprising an array of buttons  140 , and a touch screen  250 A as described in relation to  FIG. 2 . An external charging interface  158  is provided on a side panel of the housing of the apparatus  102 . The touch screen, as with most conventional Portable Digital Assistants (PDAs), both accepts input through strokes or taps and produces output for viewing by the user. Status information and commands may be entered by the user tapping on or dragging on the touch screen  250 A. 
     By way of example but not limitation, the accessory  100  includes, in the illustrated embodiment, an array of electrical contacts  353  comprising at least a portion of the financial token internal interface  145 . When the token  300  is fully inserted  322  into the cavity of the accessory housing  102 , the contacts  353  proximally engage with the contacts  350  on the token  300 , thereby establishing electrical connectivity. As described below other implementations of the internal interface  145  with the token  300  are possible, whereby electrical coupling between the token  300  and the accessory  100  are accomplished using all or partially contactless approaches. 
     In one implementation, the user turns on the accessory  100  by depressing an on/off button  305 , and then produces a stroke on the pad/screen  250 A by dragging a fingertip or stylus across the pad or screen area  250 A to reproduce a symbol or glyph substantially similar to a symbol pre-programmed into the integrated processor  105  and storage  110  (embedded, not shown). Once the symbol or glyph is entered by the user on the pad/screen  250 A, the processor  105  compares its features with a pre-stored graphical implementation and if the symbol&#39;s features are within a predetermined range, the accessory  100  is enabled for use, otherwise an invalid entry message is output to display  250 A and use is further inhibited until the successful glyph or symbol is entered. 
     As further explanation of the coupling between the accessory  100  and the token  300 , we return to  FIG. 1 . The accessory  100  includes an internal electrical/data port or interface  145  that is coupled to the integrated processor  105  through the signal bus  120  and to a power signal through power line  119  as described above. Since the signal bus  120  and power line  119  carry potentially bidirectional signals, data and/or power signals may flow into or out of the electrical/data interface  145 . In one implementation, a power signal is delivered to and energizes at least part of the coupled financial token  300  through the electrical data interface  145 . Using the supplied power, the financial token  300  may operate onboard circuitry to exchange data with the accessory  100 , receive commands from the accessory  100 , or charge an energy storage element embedded within the financial token  300  from the accessory&#39;s power source  150 . Through the interface, the integrated processor  105  may also determine a charge state of the energy storage element within the token, and display the status in the user interface  130 . Also, memory  310  within the financial token  300  may be queried through commands issued by the bus  120  through the interface  145 , and the processor  105  may receive and process the results of the data returned through the interface  145 . For example, but not by way of limitation, the processor  105  may request data regarding a financial account from the financial token  300 , and the accessory  100  may conduct a transaction using the external interface  137 , in lieu of conducting the transaction using only the financial token  300 . As another example, but not by way of limitation, the processor  105  may send commands and account data to the financial token  300 , configuring the token  300  for use for a particular account as selected through the user interface  130 . 
     The internal port or interface  145  may be coupled to a financial token  300  by any number of electrical coupling techniques, including electrical contacts between the accessory  100  and the financial token, RFID signal transceivers, IrDA signal infrared transceivers, visible light transceivers, invisible light transceivers, magnetic strip read/write heads, modulated laser transceivers, modulated RF communication transceivers, and combinations thereof. Those of skill in the relevant arts appreciate that a combination of coupling techniques may be utilized, such as by providing a data signals through electrical contacts while a power signal is delivered by an electromagnetic field from the accessory  100  to an inductor located within the token  300 . 
     Turning to  FIG. 4 , another implementation of an accessory  100  is shown with a financial token  300 . The token  300  has an embedded processor  305 , a memory  310 , and an energy storage element  451  such as a thin film capacitor electrically coupled to the token&#39;s electronic circuitry. The token  300  has a magnetic stripe  430 , which like conventional magnetic stripe fields, is readable by preexisting merchant POS terminals or ATMs. The magnetic stripe  330  may optionally be programmable by data and commands sent from the an embedded processor within the token  305  and memory  310 . 
     Similarly to  FIG. 3 , the token  300  may be placed within the accessory  100  by, for example, but not by way of limitation, sliding  322  the token  300  into a slot  323  defining a cavity within the accessory housing  102 . The accessory housing  102  retains the token  300  until the user actuates a hardware mechanism such as a latch (not shown) that retains the token  300  within the cavity within the accessory housing  102 . Alternatively, the token  300  could be retained by an electromechanical latch (not shown) coupled to the power source  150  and the integrated processor  105 , wherein the token could be released upon an execution of a command by the processor  105 . For example, but not by way of limitation, if a user entered a valid authorization code into the touch screen interface  250 A, the processor determines the code is valid and provides a command to the electromechanical latch to release the token from the accessory. Alternatively, a drive element (such as those that actuate Compact Disk player disk slots in portable CD players) could eject the card through the slot  323  upon receiving a command to eject the card from the processor  105 . 
     In this implementation, the accessory  100  includes an internal set of electromagnetic read and/or write heads  450  which comprise one possible embodiment of the electrical/data interface  145 . As the token  300  is moved  322  into the cavity  323 , the heads  450  traverse a significant portion of the length of the magnetic stripe  430  while in proximity to the surface of the magnetic stripe. If the heads  450  are so enabled by the integrated processor  105 , data may be read from and/or written to the magnetic stripe  430  during insertion  322  or extraction of the token  300 . Such data, as mentioned previously is processed by the integrated processor  105  by transmitting the data to or receiving the data from the data bus  120  which is in turn coupled to the internal interface  145 . In one example, but not by way of limitation, the token&#39;s magnetic stripe  430  is erased by the read/write heads  430  upon insertion  322  to the accessory  100 , and is programmed with account data specified in the user interface  140  upon removal of the token  300  from the accessory. 
     Also shown on the card  300  is an optional array of physical contacts  350 , which, as described above come into proximity with internal electrical contacts  353  when the token  300  is inserted  322  into the cavity  323 . The contacts  353  comprise at least a portion of the financial token internal interface  145 . When the token  300  is fully inserted  322  into the cavity of the accessory housing  102 , the contacts  353  proximally engage with the contacts  350  on the token  300 , thereby establishing electrical connectivity. As mentioned previously, other implementations of the internal interface  145  with the token  300  are possible, whereby electrical coupling between the token  300  and the accessory  100  are accomplished using all or partially contactless approaches. 
     Turning to  FIG. 7A , an alternate implementation of the accessory  100  is shown as a communications device such as a cell phone. The accessory housing  102  includes a slot  323  for a financial token  300 , or optionally, the financial token  300  is permanently or semi-permanently integrated within the hardware of the accessory  100 . The accessory  100  has a display  230 , and a data entry keypad  140 , allowing interaction with the accessory to issue user commands. As mentioned previously, the accessory  100  may be used to complete a financial transaction without removing token  300 , or the accessory  100  may configure the token  300 , using commands entered through the user interface  140 , to select a particular transaction payment account to be transmitted to the token through the internal electrical interface (not shown). In a similar spirit,  FIG. 7B  illustrates another implementation of the accessory  100 , shown as a consumer device such as a personal digital assistant (PDA). The accessory housing  102  includes a slot  323  for a financial token  300 , or optionally, the financial token  300  is permanently or semi-permanently integrated within the hardware of the accessory  100 . The accessory  100  has a touch screen display  250 A for entry and output of commands and data, a data buttons and pads  140 . As mentioned above, the accessory  100  may also be used to complete a financial transaction without removing token  300 , or the accessory  100  may configure the token  300 , using commands entered through the user interface  140 , to select a particular transaction payment account to be transmitted to the token through the internal electrical interface (not shown). 
     The above description of the disclosed embodiments is provided to enable any person of ordinary skill in the art to make or use the disclosure. Various modifications to these embodiments will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.