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                                                                   EXHIBIT 10.26

                                                         STRICTLY CONFIDENTIAL

                                    Agreement

                                     BETWEEN

                      NATIONAL DISCOUNT BROKERS CORPORATION
                                       AND

                         AETHER SYSTEMS INC. ("AETHER")

This Agreement (the "Agreement") is effective as of November 4th, 1999 (the
"Effective Date"), by and between National Discount Brokers Corporation, a New
York corporation ("National Discount Brokers"), having its principal place of
business at, New York, New York and Aether Systems, Inc., a Delaware corporation
("Aether"), having its principal place of business at 11460 Cronridge Drive,
Suite 160, Owings Mills, Maryland 21117.

National Discount Brokers Corporation and Aether hereby enter into a definitive
and binding contractual agreement for purposes of the development,
implementation, sale and support of a wireless financial data access and trading
product for sale to persons who have brokerage accounts with National Discount
Brokers (the "Subscribers") and who reside within the United States of America
hereto (the "Territory"). The product which is described in Schedule A hereto
shall for the purposes of the Agreement be known as "National Discount Brokers
Wireless Product" (the "Product") and would provide the Subscribers with mobile
device access to real-time National Discount Brokers' account, trading and
financial market information. The Product would initially source data from
National Discount Brokers host computer systems along with market data and news
from Reuters SelectFeed Plus platform, or such additional or replacement feeds
product(s) as mutually agreed to by National Discount Brokers and Aether (the
"National Discount Brokers Service").

1 Term.

The Agreement shall take effect on the Effective Date, continue for two years,
and shall automatically renew thereafter for additional one year terms, unless,
prior to any additional one year term, either party provides the other party
sixty (60) days' prior written notice of termination. Ninety(90) days prior to
the termination or expiration of the Agreement, the parties agree to negotiate
in good faith the terms and conditions of a licensing agreement for National
Discount Brokers to use Aether's intellectual property relating to the National
Discount Brokers Service and the Product.

2 RESPONSIBILITIES OF AETHER.

System Development
a)     Aether shall be responsible for all development activity associated with
the wireless data system (the "System") necessary for operation and delivery of
the Product including, but not limited to application software development,
network development and integration.

Software Development
b)     Aether shall be responsible for all custom software development required
to support the Product including, but not limited to host system interface,
application development and network interface.

Network Operations
c)     Aether shall manage, operate and maintain the System in accordance with
specifications and service levels to be agreed to by the parties hereto, which
shall include, but not be limited to, network management, operational
management, and the day-to-day operating environment.


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Hardware
d)     Aether shall initiate and maintain relationships with all hardware
vendors on favorable terms. Hardware selected shall meet the specifications to
be agreed upon by the parties hereto. Aether shall arrange for maintenance and
repair of the same, and will provide the National Discount Brokers Service in
accordance with standards to be agreed upon by the parties hereto.

Billing/Order Entry
e)     Aether shall develop, implement and maintain order-entry and billing
systems for the Product. These systems shall provide administration,
permissioning and depermissioning.

Customer Support Vendor Relations
f)     Aether shall develop, implement and manage customer support including but
not limited to, 8:30 AM -- 8:00 PM EST Monday through Friday, and shall manage
and coordinate relationships with third party suppliers such as airtime
providers and hardware vendors. Aether agrees to implement 24/7 customer service
within 6 months from execution of the Agreement.

Third Party Agreements
g)     Aether shall obtain any and all licenses and consents, and enter into and
comply with any applicable third party agreements, as may be necessary to
fulfill its obligations under the Agreement, including but not limited to
Exchange Agreements with the New York Stock Exchange, American Stock Exchange
and the Nasdaq

Subscriber Exchange Fees
h)     Aether shall be responsible for obtaining any exchange fees associated
with the receipt of real time market data on a Subscriber basis from the
individual Subscribers.

Marketing Campaign
i)     Aether Systems shall commit to investing a minimum of $500,000 in
       an advertising campaign to support the launch of the Product by
       National Discount Brokers. The $500,000 may include the value of
       advertising provided by various Aether associates. Aether will also
       use its best efforts to obtain additional advertising dollars for
       this launch through is strong association with carriers and
       hardware manufacturers.

3  RESPONSIBILITIES OF NATIONAL DISCOUNT BROKERS.

Exclusivity
a)     National Discount Brokers agrees that Aether shall be its exclusive
       provider of the Product to National Discount Brokers for the term of the
       Agreement.
Should hardware devices and or transport protocols emerge during the
term of the Agreement that may prove attractive to National Discount Brokers or
its customers, National Discount Brokers will so notify Aether in writing (the
"Competition Notice"). Aether shall have the right of first refusal to provide
said device or services (a "Competitive Service"), on terms which are the same
or better than those available to National Discount Brokers or its competitors
for the Competitive Service. National Discount Brokers shall obtain an estimate
if possible from any provider of the Competitive Service. Aether would then
provide National Discount Brokers an estimate to provide the service or device
which is the same as the Competitive Service within thirty days of Aether's
receipt of the Competitive Notice. If Aether's price and terms for the
Competitive Service are the same or better than that of the provider of the
Competitive Service to National Discount Brokers, then National Discount Brokers
shall select Aether to provide the Competitive Service. If Aether fails to
deliver to National Discount Brokers the Competitive Service at the price and
terms which are the same as or better than those made available to National
Discount Brokers or its competitors within the thirty day period after the
Competitive Notice, the provisions of this paragraph 3(a) shall be terminated
and Aether's right of first refusal shall be terminated.


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Tools and Documentation

a)     National Discount Brokers shall provide to Aether , at no charge, all
required software, tools, and documentation required to permit the Product
through the communications structure of Aether to communicate with the computer
system of National Discount Brokers.

DataFeeds
b)     National Discount Brokers shall grant to Aether a non-exclusive,
non-transferable license to receive and distribute the National Discount Brokers
Service information through the Product only within the Territory. Aether shall
receive the National Discount Brokers Service during the term of the Agreement
without payment of subscription fees and installation costs.

Telecommunication Equipment
c)     National Discount Brokers shall provide all communication lines and
equipment required to provide for communication from the National Discount
Brokers computer to the Aether computer and visa versa. National Discount
Brokers shall transmit the National Discount Brokers Service to Aether free of
any telecommunication charges. National Discount Brokers shall maintain a
development, environment to permit the testing of new features on the Product
without interruption of the National Discount Brokers Service.

Sales and Marketing
g)   In consideration of Aether having developed the System at its own
     expense and its undertaking not to seek compensation for said development
     costs from National Discount Brokers, National Discount Brokers commits
     itself to a marketing and advertising campaign for the product that is
     representative of its normal business practices for similar products.
     National Discount Brokers shall commit itself to soliciting news, and print
     media attention to the impending Product release and subsequent to that
     release date. National Discount Brokers shall define and document a
     marketing and sales plan illustrating a commitment of no less than $500,000
     over the course of the first year to the Product launch. This plan shall be
     developed within the first month after activation of the Agreement. It is
     agreed that National Discount Brokers will have the final approval on the
     creative copy and ad placement. National Discount Brokers will display at a
     minimum the Aether Logo and the phrase powered and engineered by Aether
     Systems Inc. National Discount Brokers' commitment under this paragraph (d)
     during the term of the Agreement shall not exceed $500,000.

Product Launch Plan
e)     National Discount Brokers shall budget, develop and implement marketing
and sales plans which shall include, but not be limited to, product launch
schedules, beta test program Subscriber identification, beta testing, marketing
materials, sales projections, sales force training, and public relations
releases. The plan shall be developed as part of an agreed to Product
development plan and schedules.

Future Requirements
f)     National Discount Brokers shall cooperate in the identification and the
development of mutually agreed to Product enhancements.

Trading Fees
g)     National Discount Brokers shall be responsible for any trading fees
associated with the Product.

h)     National Discount Brokers shall as part of its normal course of
       promotion for products and services, add the information regarding
       the Product to its internet site in the manner it determines in its
       sole discretion.. Aether shall provide a companion web site for
       Product information, Product ordering, and customer support.


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4            COOPERATION.

Roles and Responsibilities
a)     National Discount Brokers and Aether agree to reasonably cooperate with
one another to facilitate the achievement of their respective responsibilities,
and to document, as necessary, all relevant plans, schedules, models and
procedures mentioned above. Aether and National Discount Brokers shall assign a
project manager for the term of the Agreement.

Future Development
b)     All upgrades, modifications, enhancements to the Product, the System, the
Software, National Discount Brokers Service and the use of other devices shall
be mutually agreed upon in writing by the parties hereto before any work
commences. The parties hereto shall decide, on a case by case basis, the source
of funds for such upgrades, modifications and enhancements. Aether agrees to
provide upgrades of the Product and the System to National Discount Brokers and
its Subscribers on the same terms and conditions as such enhancements are made
available to other third parties.

Hardware Purchase
c)     National Discount Brokers shall retain the right upon (90) day written
notice to contract for and purchase all hardware for the Product for sale to
Subscribers. National Discount Brokers shall assign any applicable warranties
from hardware vendors to the Subscribers.

Insurance
d)     Should National Discount Brokers execute its right to purchase hardware
during the term, National Discount Brokers will maintain sufficient insurance
coverage for the inventory of hardware stored at Aether to recover the value of
the hardware in the event of damage, loss or theft. Aether shall take reasonable
commercial precautions to safeguard the hardware inventory stored by it.

Training
e)     National Discount Brokers and Aether will jointly work towards a plan
whereby both parties hereto may participate where appropriate in an onsite
training session with the National Discount Brokers customer service
organization. National Discount Brokers shall undertake to establish an ongoing
training cycle in accordance with National Discount Brokers normal practices.
Aether shall also provide phone support to National Discount Brokers for
training purposes.

Devices
f)     National Discount Brokers and Aether agree to develop this application on
Palm and Windows CE devices. Aether and National Discount Brokers shall decide,
on a case by case basis, the source of funds for such new devices, product
upgrades, system modifications and application enhancements.

Subscriber/ User Manual
g)     Aether will where practical supply National Discount Brokers with a user
guide for Subscribers in sufficient quantities so as to meet demand.



5             OWNERSHIP.

      Software
a)     National Discount Brokers and Aether agree that the System along with all
source code required to provide financial information to Subcribers hardware
device ("the Software") shall be the property of Aether ; provided however any
software that resides on computer or othe hardware owned, leased or used by
National Discount Brokers shall not be deemed to be Software.

Trademark
b)     National Discount Brokers and Aether agree to "brand" the Product which
trademark shall be the property of National Discount Brokers. National Discount
Brokers has the responsibility for any and all legal costs associated with
trademarking the name.


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6             FINANCIALS.

Monthly Fees
a)     In consideration of Aether being responsible for managing the Subscriber
provisioning, permissioning, activation, customer service, network and systems
management, technical support, software development, billing, collections,
managing carrier relationships, and managing airtime, Aether will charge a
monthly fee to Subscribers inclusive of the above mentioned items for $69.00 per
month. Aether will also bundle much of its current financial news service
("MarketClip(TM)") functionality along with email and internet access per its
ownership in AirWeb Corporation doing business as Opensky into the National
Discount Brokers application free of any additional fees.

Hardware Costs
b)     In consideration of Aether having developed the Product in accordance
with National Discount Brokers requirements and choice of platform delivery
mechanisms, Aether shall charge the Subscribers according to the current market
price of the device(s).

Aether shall undertake (within 30 days of written notification) to reduce the
price of Subscriber hardware to a price not greater than the vendor's published
price schedule that reflects a deduction in price for the aforementioned
hardware models.

New Hardware Models
Aether shall advise National Discount Brokers from time to time as to the
upcoming release of new hardware models and advise National Discount Brokers as
to the efficacy of adopting the new model as the defacto hardware for
Subscribers.

Subscriber Term
Each Subscriber shall enter into a one year agreement for the National Discount
Brokers Service. Should the Subscriber at any time after an initial 15 day trial
decide to cancel the National Discount Brokers Service the Subscriber shall be
held accountable for payment of 75% of the remaining contract fees.

Subscriber Exchange Fees
c.)     It is understood that exchange fees associated with the receiving of
real time market data shall be paid by the Subscriber and are in addition to the
monthly fees.

Trading Fees
d)     National Discount Brokers shall be responsible for any trading fees other
than payments for real time quotes associated with subscribers using the System.
Activation
h)     Aether shall be entitled to receive a one time activation and
       handling fee of $69.00 per new Subscriber to be paid by the Subscriber.
i)     Aether agrees that Subscribers will be entitled to receive and will
       receive the Product on the best terms and conditions, including the
       monthly service charge, that Aether makes the Product (or similar
       device and service) available to other persons from time to time.
       The foregoing most favored nation clause shall not apply to short
       term introductory programs of Aether or where the functionality or
       level of service offered is materially different
j)     Aether and National Discount Broker agree to jointly work on
       developing a lower price point wireless product offering for NDB
       customers. During the first month of performance of this Agreement,
       the parties shall establish a plan encompassing various hardware
       and software solutions that will incorporate a lower price point
       product being made available to National Discount Broker customers.
       (It is understood that a lower price point product offering will
       likely necessitate having reduced functionality, usage and response
       limitations for the user.

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k)     The parties shall mutually agree to the plan to develop the low cost
       solution referred to in the above paragraph (j). After the plan is
       developed, the parties shall pursue sufficient funding to implement the
       plan.

7           CONFIDENTIALITY.

a)     Each party hereto acknowledges that it has received, and will during the
       term of the Agreement, receive confidential or proprietary information
       regarding the business or products of the other party hereto. Each party
       hereto will maintain the confidentiality of such information, provided
       that it is designated in writing as confidential, proprietary, or marked
       with words of similar import, or if orally conveyed, is reduced to
       writing and delivered to the receiving party by the disclosing party
       within 10 days of oral conveyance. Each party hereto agrees that if the
       proposed transaction is not consummated for any reason, it will return to
       the other party hereto all confidential material or information without
       retaining any copies thereof.

b)           Confidential information shall not include information which:

             i)          at or prior to the time of disclosure by the disclosing
party was known to the receiving party;
             ii) at or after the time of disclosure by the disclosing party
becomes generally available to the public other than through any act or omission
on the receiving party's part;
             iii) is developed by the receiving party independent of any
confidential information it receives from the disclosing party;
             iv) the receiving party receives from a third party free to make
such disclosure without breach of any legal obligation; or
              v) is required to be disclosed pursuant to any order, subpoena or
document discovery request.

8           EXCLUSIVITY.

             Aether from the effective date of the Agreement shall not license
any rights to the executable software and source code that constitutes the
National Discount Brokers specific back office trading and account management
interfaces, to any competitor of National Discount Brokers for the purpose of
the wireless transmission of National Discount Brokers information. This
capability is embodied and implemented within a single software library, titled,
National Discount Brokers.dll. It is understood that Aether having bundled
MarketClip(TM) and Opensky functionality into the Product that functionality
shall not be considered part of this exclusivity clause. Aether has retained
full rights to the MarketClip and Opensky products and shall NOT be bound or
restricted in its ability to market the product to National Discount Brokers
competitors. It is also understood that Aether has utilized Aether's proprietary
Aether Intelligent Messaging executable software components ("AIM(TM)") and
source code(AIM(TM)) in the Product that AIM(TM) shall not be considered part of
this exclusivity clause. Aether has retained full rights to the AIM(TM) product
and shall NOT be bound or restricted in its ability to market the Product to
National Discount Brokers competitors.

9           LIABILITY

Aether shall not be liable for any entered order, trade account or position
inquiry by a Subscriber or user of the device that results in financial loss or
injury to the respective client or holder of said account.

NEITHER PARTY HERETO SHALL BE LIABLE FOR ANY SPECIAL, INCIDENTAL, INDIRECT
AND/OR, CONSEQUENTIAL DAMAGES OF ANY KIND, RESULTING FROM EITHER PARTY'S
PERFORMANCE OR FAILURE TO PERFORM PURSUANT TO THE TERMS OF THE AGREEMENT OR
RESULTING FROM THE FURNISHING, PERFORMANCE OR USE OR LOSS OF ANY LICENSED
PRODUCTS OR OTHER MATERIALS DELIVERED TO NATIONAL DISCOUNT BROKERS THEREUNDER,
INCLUDING WITHOUT LIMITATION ANY INTERRUPTION OF BUSINESS, WHETHER RESULTING
FROM BREACH OF CONTRACT OR BREACH OF WARRANTY, EVEN IF THE PARTIES HERETO HAVE
BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

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10     PRESS RELEASES.

Neither Aether nor National Discount Brokers or their respective affiliates
shall issue any press release or make any other public statement relating to the
Agreement unless required by law, regulation, court order or the rules of any
applicable stock exchange or regulatory authority or approved in writing by the
other party.

National Discount Brokers agrees to make press releases and public relations
announcements of its impending release of the National Discount Brokers Wireless
Trading System application upon completion of its internal QA cycle. National
Discount Brokers also acknowledges that Aether may make certain statements as
the relationship at its forthcoming IPO roadshow. National Discount Brokers may
at its discretion choose to have Aether undertake to coordinate that effort on
its behalf subject to any National Discount Brokers internal approval processes.

11     TERMINATION.

a)     Termination for Breach. If a party (the "Defaulting Party") is in
material breach of or default under this Agreement, and the Defaulting Party
does not remedy that breach or default within thirty (30) calendar days after
receipt from the other party of written notice of that default or breach, the
other party shall after the expiration of such thirty (30) calendar day period
have the right to terminate this Agreement unless the Defaulting Party has
commenced steps to remedy such breach or default and effects a cure within
thirty (30) days of receipt of the default notice.

Termination in Event of Bankruptcy. Either party may terminate the Agreement at
any time by written notice in the event that the other: (i) files a voluntary
petition in bankruptcy or under any similar insolvency law; (ii) makes an
assignment for the benefit of creditors; (iii) has filed against it any
involuntary petition in bankruptcy or under any similar insolvency law if any
such petition is not dismissed within sixty (60) days after filing; or (iv) has
a receiver appointed for, or a levy or attachment made against, substantially
all of its assets, if any such petition is not dismissed or such receiver or
levy or attachment is not discharged within sixty (60) days after the filing or
appointment.

12)    Assignment

Notwithstanding any other terms of the Agreement, National Discount Brokers
may, subject to Aether's prior consent which consent will be not unreasonably
withheld, transfer the Agreement to its parent organization National Discount
Brokers Group, Inc. and hereby agrees to provide Aether reasonable notice of
any such transfer. Aether may assign the Agreement to any successor to its
business

13)    Governing Law

The Agreement shall be governed by New York law without regard to conflicts of
law principle

NATIONAL DISCOUNT BROKERS CORPORATION              AETHER SYSTEM INC.

/s/ SAMIR SHAH                             /s/ DAVID S. OROS
-------------------------------------      -----------------------------------
              Signature                                 Signature

SAMIR SHAH CO-CHIEF OPERATING OFFICER        DAVID S. OROS   PRESIDENT/CEO
-------------------------------------      -----------------------------------
      Name and Title (printed)                   Name and Title (printed)

               11/4/99                                   11/8/99
-------------------------------------      -----------------------------------
                Date                                       Date




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                                  SCHEDULE "A"

          "The Product" shall be identified as any real-time market and delayed
          data/news information and or pertinent brokerage account information
          that can be delivered wirelessly between NDB and their customers(s)
          and from customer(s) to NDB through use of the following hardware
          device(s):

          Palm Devices
          CE Devices
          RIMM Pagers
          WAP (wireless application protocol) enabled phones
          VISOR Devices

           *DOES NOT INCLUDE NDB IVR

               /s/ Samir Shah 11/4/99
             Co-Chief Operating Officer