Patent Publication Number: US-2009240696-A1

Title: Method and system for providing contents to an off-line mobile storage device

Description:
The present invention relates generally to information and commerce distribution and, more particularly, to a method and system for providing contents to an off-line mobile storage device. 
     Many information providers are available on-line for providing downloadable content for purchase by users. These on-line content providers typically require users to access them on-line in order to purchase the content. Thus, in order to purchase and download new content, the user must have on-line access. 
     Generally, users are also required to have on-line access to the content providers in order to browse through the content providers&#39; available content and select which content the user desires to purchase. In addition, once the content is purchased, the user has to wait for the purchased content to be downloaded, which may result in long delays before the user is able to use the content. 
     In accordance with the present invention, a method and system for providing contents to an off-line mobile storage device are provided that substantially eliminate or reduce disadvantages and problems associated with conventional systems and methods. 
     According to one embodiment of the present invention, a method for providing contents to an off-line mobile storage device is provided. The method includes determining that a mobile storage device is accessing a content provider in a first on-line session. The content provider comprises a content database that is inaccessible to the mobile storage device when the mobile storage device is off-line. A first set of contents is selected from the content database for storing as hidden contents on the mobile storage device during the first on-line session. 
     According to another embodiment of the present invention, a method for providing contents to an off-line mobile storage device is provided that includes accessing a content provider with the mobile storage device in a first on-line session. The content provider comprises a content database that is inaccessible to the mobile storage device when the mobile storage device is off-line. A plurality of contents is received from the content database at the mobile storage device. The contents are stored as hidden contents on the mobile storage device. 
     According to yet another embodiment of the present invention, a mobile storage device is provided that includes a content memory and a content controller. The content memory is operable to store a plurality of hidden contents and a plurality of accessible contents. The content controller is operable to convert the hidden contents into accessible contents. 
     Technical advantages of one or more embodiments of the present invention include providing a method for providing contents to an off-line mobile storage device. In a particular embodiment, while the mobile storage device is on-line, contents are stored on the mobile storage device as hidden contents that are inaccessible to the user of the mobile storage device. When the mobile storage device is later off-line, the user may select one or more of the hidden contents for purchase. The mobile storage device then allows the selected contents to become accessible to the user. The user may complete the purchase at a later time when the mobile storage device has on-line access again. As a result, new contents may be made available to the user even when the mobile storage device is off-line. In addition, the user does not have to wait for the new contents to be downloaded because the contents are already stored in the mobile storage device. 
     Other technical advantages will be readily apparent to one skilled in the art from the following figures, description, and claims. 
     Before undertaking the DETAILED DESCRIPTION, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. In particular, a controller may comprise one or more data processors, and associated input/output devices and memory, that execute one or more application programs and/or an operating system program. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
    
    
     
       For a more complete understanding of the present invention and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts, in which: 
         FIG. 1  is a block diagram illustrating a system operable to provide contents to an off-line mobile storage device in accordance with one embodiment of the present invention; 
         FIG. 2  is a block diagram illustrating one of the mobile storage devices of  FIG. 1  in accordance with one embodiment of the present invention; 
         FIG. 3  is a flow diagram illustrating a method for providing contents to an off-line mobile storage device from the perspective of the mobile storage device of  FIGS. 1 and 2  in accordance with one embodiment of the present invention; and 
         FIG. 4  is a flow diagram illustrating a method for providing contents to an off-line mobile storage device from the perspective of the hidden content manager of  FIG. 1  in accordance with one embodiment of the present invention. 
     
    
    
       FIGS. 1 through 4 , discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged system for providing downloadable contents. 
       FIG. 1  is a block diagram illustrating a system  100  operable to provide contents to an off-line mobile storage device  102  in accordance with one embodiment of the present invention. The system  100  comprises a plurality of mobile storage devices (MSDs)  102 , a plurality of bases  104  for providing access to a network  106  for the mobile storage devices  102 , at least one content provider  108  for providing contents to the mobile storage devices  102 , a hidden content manager  110  for selecting contents to be downloaded into the mobile storage devices  102 , and the network  106 , which provides communication between the mobile storage devices  102  (through the bases  104 ), the content provider  108 , and the hidden content manager  110 . It will be understood that the system  100  may comprise any other suitable components, such as servers coupled to the network  106 , without departing from the scope of the present invention. 
     Each mobile storage device  102  may comprise a hard disk-based consumer electronic product, such as an HDD100 or an HDD60 manufactured by Philips or an iPod manufactured by Apple, a laptop computer, or any suitable device capable of receiving contents from the content provider  108  through the network  106  and a base  104  and storing those contents. As used herein, “each” means every one of at least a subset of the identified items, and “content” means video data, audio data and/or other suitable data that is operable to be executed, displayed, or otherwise operated on a mobile storage device  102 . For example, contents may include songs, videos, e-books, computer software and the like. 
     For one embodiment, each mobile storage device  102  may be operable to communicate with other mobile storage devices  102 , a base  104  and/or the network  106  over a wireless interface. The wireless interface may comprise communication channels defined upon radio links, such as an Enhanced Data for GSM (Global System for Mobile communications) Evolution interface, a Wideband Code Division Multiple Access interface, a WiFi interface, an Ultra Wide Band interface, or any other suitable interface. 
     Each mobile storage device  102  comprises a content controller  120  for controlling contents in the device  102  and a content memory  122  for storing contents in the device  102  (as illustrated in the mobile storage device  102   a ). As described in more detail below in connection with  FIG. 2 , the content controller  120  is operable to manage the contents stored in the content memory  122 , to convert hidden contents into limited and/or unlimited contents, and to synchronize the mobile storage device  102  with another device, such as another mobile storage device  102 , a personal computer or any other suitable device. 
     Each base  104  is operable to provide a physical connection for a mobile storage device  102  to communicate with the network  106 . Each of the bases  104  may comprise a device to which the mobile storage device  102  may be directly coupled or to which the mobile storage device  102  may be indirectly coupled, such as through a cable or over a wireless interface. In addition, each of the bases  104  is coupled to the network  106 . Thus, the mobile storage devices  102  are operable to communicate with the network  106  through the bases  104 . 
     It will be understood that the bases  104  may be coupled to the network  106  through a personal computer or any other suitable component without departing from the scope of the present invention. Also, although the illustrated embodiment comprises three mobile storage devices  102   a - c  and three corresponding bases  104   a - c , it will be understood that the system  100  may comprise any suitable number of mobile storage devices  102  and corresponding bases  104  without departing from the scope of the present invention. 
     The content provider  108  is coupled to the network  106  and is operable to provide contents to the mobile storage devices  102 . The content provider  108  comprises a content database  114  that is operable to store a plurality of contents that may be purchased by users and downloaded to the mobile storage devices  102 . Thus, as described in more detail below, the content provider  108  is operable to provide one or more of the contents stored in the content database  114  to the mobile storage devices  102  through the network  106 . The system  100  may comprise any suitable number of content providers  108 , each of which may be operable to provide contents for one or more business entities. 
     The hidden content manager  110  is coupled to the network  106  and is operable to manage contents in the system  100  by selecting contents from the content database  114  of the content provider  108  to be downloaded and stored in the content memories  122  of the mobile storage devices  102 , as described in more detail below. Although illustrated as a separate component, it will be understood that the hidden content manager  110  may also be implemented elsewhere, such as a part of the content provider  108 , as a part of the mobile storage devices  102  and/or as a part of a central server or any other suitable entity without departing from the scope of the present invention. Thus, for example, the content provider  108  may comprise the hidden content manager  110 , the content provider  108  may be coupled to the hidden content manager  110 , which may or may not be directly coupled to the network  106 , the content controllers  120  of the mobile storage devices  102  may each comprise a hidden content manager  110 , a combination of these, or any other suitable configuration may be implemented. 
     In one embodiment, the network  106  comprises a packet data network, such as the Internet, or other suitable network. However, the network  106  may also comprise any interconnection found on any computer network such as a local area network (LAN), a wide area network (WAN), or any other communications and data exchange systems created by connecting two or more computers. 
     Each base  104 , the content provider  108 , and the hidden content manager  110  are operable to communicate with the network  106  over communication lines  130 , which may be any type of communication link capable of supporting data transfer. In one embodiment, the communication lines  130  may comprise, alone or in combination, Integrated Services Digital Network (ISDN), Asymmetric Digital Subscriber Line (ADSL), T1 or T3 communication lines, hardwire lines, or telephone links. It will be understood that the communication lines  130  may comprise other suitable types of data communication links. The communication lines  130  may also connect to a plurality of intermediate servers between the network  106  and the bases  104 , the content provider  108 , and the hidden content manager  110 . 
     In operation according to one embodiment, a user of a mobile storage device  102  accesses the content provider  108  through the network  106 . The content provider  108  then presents a plurality of content identifiers, each of which is operable to identify a content stored in the content database  114 , for selection by the user. The content provider  108  may also provide any suitable features, such as the ability to search the contents in the content database  114  based on keywords, subject matter and/or any other suitable searching options. 
     After the user selects one or more contents for purchase, the content provider  108  may request payment information, such as credit card or other suitable authentication information, and allow the user to download the purchased content(s) to the mobile storage device  102  upon verification of the payment information. In addition, according to one embodiment, the content provider  108  may allow the user to create a wish list of contents that the user is interested in purchasing but does not want to purchase at the present time. 
     While the user is browsing the available contents, according to one embodiment, the hidden content manager  110  stores some of the contents from the content database  114  in the content memory  122  of the mobile storage device  102  as hidden contents. For an alternative embodiment, the hidden content manager  110  communicates the contents for storage on the mobile storage device  102 . 
     The hidden contents are inaccessible by the user unless purchased. For example, the hidden contents may be encrypted or stored in any other inaccessible manner. Thus, when the user is off-line, the user may choose to purchase a content that is stored as a hidden content, at which time the content controller  120  allows the user to access the content, as described in more detail below. For example, if the hidden content is encrypted, the content controller  120  decrypts the content such that the content becomes accessible by the user. 
     The hidden content manager  110  may select the hidden contents that are to be stored on the mobile storage device  102  based on the user&#39;s browsing habits, the user&#39;s wish list, the user&#39;s profile, the mobile storage device&#39;s  102  usage profile, promotions provided by the content provider  108  and/or any other suitable information. In this way, the contents that are most likely to be purchased by the user may be selected and made available for off-line purchase. 
       FIG. 2  is a block diagram illustrating one of the mobile storage devices  102  in accordance with one embodiment of the present invention. The mobile storage device  102  comprises a content controller  120  and a content memory  122 . The content memory  122  is operable to store a plurality of accessible contents  202 , a plurality of hidden contents  204 , and a catalog  206 . The content memory  122  may also be operable to store an on-line purchase list  210  and a wish list  212 , in addition to any other suitable data. The accessible contents  202  comprise unlimited contents  220  and, for one embodiment, may also comprise limited contents  222 . It will be understood that the mobile storage device  102  may comprise any other suitable components in order to store and provide the contents to the user, such as a speaker, a video screen and/or other suitable components. 
     The content controller  120  is operable to manage the contents  202  and  204  stored in the content memory  122 , to convert hidden contents  204  into accessible contents  202 , and to synchronize the mobile storage device  102  with another device, such as another mobile storage device  102 , a personal computer or any other suitable device. For one embodiment, the content controller  120  is also operable to convert limited contents  222  into unlimited contents  220 . 
     The content controller  120  is also operable to overwrite hidden contents  204  with other contents purchased and downloaded by the user, which are stored as accessible contents  202  in the content memory  122 . According to one embodiment, the hidden content manager  110  is operable to determine an order of priority for overwriting the hidden contents  204  and to notify the content controller  120  of the order of priority. For an alternative embodiment, the content controller  120  is operable to determine in which order to overwrite the hidden contents  204 . 
     The unlimited contents  220  comprise contents that have been purchased and are available to the user. For example, for an embodiment in which the mobile storage device  102  comprises an audio jukebox, the unlimited contents  220  comprise songs for which the user has paid and, thus, that may be played by the mobile storage device  102  for the user at any time and any number of times. 
     The hidden contents  204  comprise contents that have been selected by the hidden content manager  110  and downloaded into the content memory  122  from the content provider  108  in a background process that is transparent to the user. The hidden contents  204  are inaccessible by the user. Thus, continuing the example in which the mobile storage device  102  comprises an audio jukebox, the hidden contents  204  comprise songs that the mobile storage device  102  will not play for the user. However, any or all of those songs may be purchased by the user even while the user is off-line and, thus, has no access to the content provider  108 . After being purchased, the content controller  120  may convert the song from a hidden content  204  into an accessible content  202  (either an unlimited content  220  or a limited content  222 , as described in more detail below). At that point, the song may be played by the mobile storage device  102  for the user. For example, for one embodiment, the hidden contents  204  may be encrypted and the content controller  120  may be operable to convert a hidden content  204  into an accessible content  202  by decrypting the hidden content  204 . 
     The optional limited contents  222  comprise contents that have been selected for purchase by the user while off-line but that have not been purchased yet. For example, for one embodiment, when a user wants to buy a hidden content  204  while off-line, the content controller  120  may convert the hidden content  204  into a limited content  222  instead of an unlimited content  220 . For the example in which the mobile storage device  102  comprises an audio jukebox, the limited contents  222  comprise one or more songs that the user has decided to purchase while off-line. These songs are made available to the user with additional restrictions as compared to songs stored as unlimited contents  220 . For example, songs stored as unlimited contents  220  may have some restrictions with regard to copying or other suitable restrictions. However, limited contents  222  are subject to additional restrictions. 
     For example, a song that is a limited content  222  may be restricted to being played a specified number of times and/or during a specified period of time before being deleted from the content memory  122 , being converted back into a hidden content  204 , or being subject to a gradual degradation in quality. It will be understood that the limited content  222  may be otherwise suitably restricted without departing from the scope of the present invention. In this way, the content may be made available on a limited basis while the user is off-line, allowing time for the user to access the content provider  108  on-line in order to complete the purchase. After the limited content  222  is actually purchased, the content controller  120  then converts the limited content  222  into an unlimited content  220 , thereby removing the additional restrictions. 
     Though shown separately, the contents  204 ,  220  and/or  222  may be implemented together in the content memory  122 . Furthermore, a content may be in the hidden contents  204 , then become one of the limited contents  222 , and finally become one of the unlimited contents  220  without being moved from one part of the content memory  122  to another. Instead, the address of the content may simply be identified as belonging to a hidden, limited or unlimited content. It will be understood that the contents may be otherwise suitably identified as hidden, limited or unlimited contents without departing from the scope of the present invention. 
     The catalog  206  comprises information about contents available for purchase from the content provider  108 . For example, the catalog  206  may comprise a listing of some or all the contents stored in the content database  114 , along with any relevant corresponding information such as price, size and the like. The catalog  206  may also identify which of the contents are stored on the mobile storage device  102  as hidden contents  204  and, thus, are available for off-line purchase. 
     The catalog  206  may also store information to identify which contents in the catalog  206  the user viewed while browsing off-line. These viewed contents, if not already a part of the hidden contents  204 , may be downloaded and stored as hidden contents  204  when the user is on-line at a later time. 
     The optional on-line purchase list  210  comprises a list of contents that the user has selected for purchase while browsing the catalog  206  while off-line, but which are not stored in the content memory  122  as hidden contents  204 . When the user later accesses the content provider  108  on-line, the content provider  108  may then provide the contents identified in the on-line purchase list  210  for purchase and download by the user. If the user declines to complete the transaction at that time, the hidden content manager  110  may select those contents as hidden contents  204  to be stored for possible future purchase. 
     The optional wish list  212  comprises a list of contents that have been identified by the user as contents that he or she may want to purchase at a later time. When the user is on-line, the hidden content manager  110  may use the wish list  212  in selecting contents to be stored as hidden contents  204  for possible future purchase. It will be understood that the wish list  212  may also be stored in the content provider  108  in addition to or instead of the mobile storage device  102 . 
       FIG. 3  is a flow diagram illustrating a method for providing contents to an off-line mobile storage device  102  from the perspective of the mobile storage device  102  in accordance with one embodiment of the present invention. The method begins at step  300  where the mobile storage device  102  accesses a content provider  108  in an on-line session. 
     At step  302 , hidden contents  204  are downloaded into the content memory  122  of the mobile storage device  102  in a background process that is transparent to the user. At step  304 , the mobile storage device  102  loses access to the content provider  108  by going off-line. At step  306 , the user accesses the catalog  206  and browses the contents listed in the catalog  206 . 
     At decisional step  308 , the content controller  120  makes a determination regarding whether or not the user has selected one of the contents listed in the catalog  206  for purchase. Although the following description refers to a single content, it will be understood that the user may select a plurality of contents for purchase without departing from the scope of the present invention. 
     If the user has not selected one of the contents listed in the catalog  206  for purchase, the method follows the No branch from decisional step  308  and comes to an end. If the user has selected one of the contents listed in the catalog  206  for purchase, the method follows the Yes branch from decisional step  308  to decisional step  310 . 
     At decisional step  310 , the content controller  120  makes a determination regarding whether or not the content selected for purchase by the user is stored in the mobile storage device  102  as a hidden content  204 . If the content selected for purchase by the user is stored in the mobile storage device  102  as a hidden content  204 , the method follows the Yes branch from decisional step  310  to optional decisional step  312 . 
     At optional decisional step  312 , the content controller  120  makes a determination regarding whether or not the hidden content  204  selected for purchase should be converted into limited content  222 . This step may be included when the optional limited contents  222  are included in the content memory  122  and the content controller  120  is able to distinguish between a trustworthy and an untrustworthy mobile storage device  102  and/or user. Thus, when the mobile storage device  102  and/or the user is identified as trustworthy, the content controller  120  determines that the hidden content  204  selected for purchase may be converted directly into an unlimited content  220 . However, when the mobile storage device  102  and/or the user is identified as untrustworthy, the hidden content  204  selected for purchase is converted into limited content  222 . Additionally, when the content controller  120  is unable to distinguish between a trustworthy and an untrustworthy mobile storage device  102  and/or user, step  312  may be omitted even when the limited contents  222  are included in the content memory  122  because the hidden content  204  selected for purchase will be converted into limited content  222  regardless of the trustworthiness of the mobile storage device  102  and/or the user. 
     If the hidden content  204  selected for purchase should be converted into a limited content  222 , the method follows the Yes branch from decisional step  312  to step  314 . As described below, steps  314 - 324  are also optional steps that are omitted for embodiments in which the limited contents  222  are not included in the content memory  122 . At step  314 , the content controller  120  converts the hidden content  204  selected for purchase into a limited content  222 . 
     At decisional step  316 , the content controller  120  makes a determination regarding whether or not a conversion requirement has been met in order to allow the limited content  222  created in step  314  to be converted into an unlimited content  220 . The conversion requirement may comprise the mobile storage device  102  accessing the content provider  108  on-line and providing payment information or any other suitable requirement. 
     If the conversion requirement has not been met, the method follows the No branch from decisional step  316  to decisional step  318 . At decisional step  318 , the content controller  120  makes a determination regarding whether or not an inaccessibility condition exists. For example, the limited content  222  created in step  314  may have been accessed more than a specified number of times and/or for longer than a specified period of time, in which case an inaccessibility condition would exist. 
     If an inaccessibility condition does exist, the method follows the Yes branch from decisional step  318  to step  320 . At step  320 , the content controller  120  responds to the inaccessibility condition. For example, the content controller  120  may delete the limited content  222  from the content memory  122 , convert the limited content  222  back into hidden content  204 , gradually degrade the quality of the limited content  222  or the like. 
     At decisional step  322 , the content controller  120  makes a determination regarding whether or not conversion is still possible for the limited content  222 . For example, if the limited content  222  is subject to a gradual degradation in quality, the content controller  120  may still be able to convert that limited content  222  into an unlimited content  220  with its quality restored after the conversion requirement has been met. However, if the limited content  222  has been deleted or converted back into hidden content  204 , the content no longer exists as limited content  222 . Therefore, conversion of the limited content  222  is no longer possible. 
     If conversion is still possible, the method follows the Yes branch from decisional step  322  and returns to decisional step  316  for a determination as to whether or not the conversion requirement has been met. However, if conversion is no longer possible, the method follows the No branch from decisional step  322  and comes to an end. 
     Returning to decisional step  318 , if an inaccessibility condition does not exist, the method follows the No branch from decisional step  318  and returns to decisional step  316  where the content controller  120  makes another determination regarding whether or not a conversion requirement has been met. 
     Returning to decisional step  316 , if the conversion requirement has been met, the method follows the Yes branch from decisional step  316  to step  324 . At step  324 , the content controller  120  converts the limited content  222  into an unlimited content  220 , and the method comes to an end. 
     Returning to decisional step  312 , if the hidden content  204  selected for purchase should not be converted into limited content  222 , the method follows the No branch from decisional step  312  to step  326 . Thus, for embodiments in which the optional limited contents  222  are not included in the content memory  122  or for situations in which the optional limited contents  222  are included in the content memory  122  and the mobile storage device  102  and/or the user is identified as trustworthy, the method follows the No branch from decisional step  312  to step  326 . At step  326 , the content controller  120  converts the hidden content  204  selected for purchase into an unlimited content  220 , and the method comes to an end. 
     Returning to decisional step  310 , if the content selected for purchase by the user is not stored in the mobile storage device  102  as a hidden content  204 , the method follows the No branch from decisional step  310  to optional step  328 . At optional step  328 , an identifier for the content selected for purchase may be stored in the on-line purchase list  210 , and the method comes to an end. In addition, if optional decisional step  312  is omitted, when the method follows the Yes branch from decisional step  310 , the method continues to step  314  if the limited contents  222  are included (in which case step  326  is omitted) and continues to step  326  if the limited contents  222  are not included (in which case steps  314 - 324  are omitted). 
       FIG. 4  is a flow diagram illustrating a method for providing contents to an off-line mobile storage device  102  from the perspective of the hidden content manager  110  in accordance with one embodiment of the present invention. Although the following description applies to how the hidden content manager  110  operates with regard to a single one of the mobile storage devices  102 , it will be understood that the hidden content manager  110  is capable of serving a plurality of mobile storage devices  102  simultaneously. The method begins at step  400  where the hidden content manager  110  determines that the mobile storage device  102  is accessing the content provider  108  in an on-line session. 
     At step  402 , the hidden content manager  110  selects contents from the content database  114  to store as hidden contents  204  in the content memory  122  of a mobile storage device  102  while the mobile storage device  102  is accessing the content provider  108  in the on-line session. The hidden content manager  110  may select the contents based on the user&#39;s browsing habits, a wish list for the user of the mobile storage device  102  such as the wish list  212 , the user&#39;s profile, the mobile storage device&#39;s  102  usage profile, promotions provided by the content provider  108  and/or any other suitable information. In this way, the contents that are most likely to be purchased by the user may be selected and made available for off-line purchase. 
     At optional step  404 , while the user is browsing the available contents during the on-line session, the hidden content manager  110  may store or communicate for storage at least a portion of the contents selected from the content database  114  in the content memory  122  of the mobile storage device  102  as hidden contents  204 . According to one embodiment, the hidden content manager  110  stores or communicates for storage as many contents as will substantially fill the available space of the content memory  122 . However, it will be understood that the hidden content manager  110  may store or communicate for storage any suitable number of contents without departing from the scope of the present invention. As an alternative, after being notified of the selected contents by the hidden content manager  110 , the content provider  108  may communicate the contents for storage and/or the content provider  108  or the content controller  120  may store the contents in the content memory  122 . 
     At optional step  406 , the hidden content manager  110  may determine an order of priority for the hidden contents  204  to be overwritten when additional space is needed in the content memory  122 . At optional step  408 , the hidden content manager  110  may notify the content controller  120  of the order of priority determined in step  406 . As an alternative, the content controller  120  may determine in which order to overwrite the hidden contents  204 . 
     At decisional step  410 , the hidden content manager  110  makes a determination regarding whether or not the mobile storage device  102  is accessing the content provider  108  in another on-line session. If the mobile storage device  102  is not in another on-line session, the method follows the No branch from decisional step  410  and remains at decisional step  410  until the mobile storage device  102  is on-line again. 
     If the mobile storage device  102  is in another on-line session, the method follows the Yes branch from decisional step  410  and returns to step  400  where the hidden content manager  110  may determine that the mobile storage device  102  is again on-line and, in step  402 , select additional contents from the content database  114  to fill any space that has become available in the content memory  122  while the mobile storage device  102  was off-line and/or to overwrite other hidden contents  204  that the hidden content manager  110  has determined are less likely to be purchased than the newly selected contents. 
     Although the present invention has been described with several embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.