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Mr. Bradford J. Richdale
864 John Anderson Drive
Ormond Beach, FL 32176

Michael M. Cimino
President, Zapp.net, Inc.
2570 West International Speedway Blvd.
Daytona Beach, FL 32114

Dear Brad and Michael:

This letter confirms our agreement relating to Summus, Ltd. and Summus
Technologies, Inc. As we discussed, we have agreed to the following:

1.       Brad Richdale personally will lend $250,000 in cash in immediately
         available funds to Summus Ltd. upon the execution of this agreement.
         Contemporaneously with payment of this $250,000 to Summus Ltd., Summus
         Ltd. will execute a convertible note for the $250,000. The note will
         bear interest at 8% per annum and will be payable from the first
         $750,000 payment regarding the Marketing Agreement referred to in
         Section 2 below. If this note is not repaid when due, you will have the
         option to convert it into 0.9% of the issued and outstanding shares of
         Summus Ltd. common stock. It is understood that the $250,000 will be
         used by Summus, Ltd. primarily to fund its operating expenses.

2.       Summus, Ltd. and High-Speed Net Solutions, Inc., currently named
         Zzap.net, Inc. ("Net Solutions") will enter into a Marketing License
         Agreement (the "Marketing Agreement") no latter than 40 days from the
         execution of this agreement. This Marketing Agreement will contain
         non-business terms and conditions substantially similar to the final
         draft of the Marketing License Agreement from December 10, 1998,
         relating to the previous ZAP transaction (the "Previous Agreement"). In
         this regard, Net Solutions will have the sublicense rights specified in
         and in accordance with the Previous Agreement. The basic business terms
         of the Marketing Agreement will be as follows:

         a.       An initial three year term. After the initial three year term,
                  Net Solutions will have the option to renew the Marketing
                  Agreement for an upfront payment per year repayable against
                  royalties of the greater of (i) $2.5 Million or (ii) 15% of
                  the prior year's royalty payments to Summus, Ltd. under the
                  Agreement. The $2.5 Million will be paid in four equal monthly
                  installments, with the first payment being made at the
                  beginning of the additional term. This upfront

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                  payment will be repaid pursuant to the same formula used in
                  the repayment of the initial $3 Million advance as stated in
                  Section 2b hereof.

         b.       Net Solutions will have an exclusive right to sell the video
                  streaming product as such product was defined in the Previous
                  Agreement, except for the government market. Summus, Ltd. will
                  also have the right to market the video streaming products in
                  the OEM market. OEM video streaming sales royalties will be
                  divided 50/50 of net, with each party recouping direct costs
                  as documented. Until New Solutions recoups the initial $3
                  Million payment for the Marketing Agreement, the royalty
                  payment shall be split 70/30 of net, with Summus, Ltd.
                  receiving 30%, and the other 20% which otherwise would be
                  payable to Summus, Ltd. being applied to pay down the $3
                  Million. Summus, Ltd. retains the exclusive rights to sell the
                  video streaming product in the government market.

         c.       Net Solutions will have a non-exclusive license to sell the
                  other products, including newly developed products, of Summus,
                  Ltd. as defined in the previous Agreement.

         d.       Summus, Ltd. will receive seven and a half percent (7 1/2%) of
                  the Adjusted Gross Revenue (as defined in the Binding Letter
                  Agreement dated October 28, 1998) generated relating to Summus
                  products by Net Solutions outside of the OEM market. The full
                  amount of this seven and one-half percent (7 1/2%) will be
                  paid to Summus, Ltd. on a monthly basis, and there will be no
                  deductions from the royalties.

         e.       The terms and conditions of any OEM sale not involving video
                  streaming in which Net Solutions has involvement, including
                  the appropriate compensation for Net Solutions and Summus,
                  Ltd, will be determined through reasonable good faith
                  negotiations between Summus, Ltd. and Net Solutions on a case
                  by case basis.

         f.       With respect to the OEM Market, Net Solutions and Summus, Ltd
                  will work together and keep one another informed so that there
                  is no duplication of effort or confusion in the marketplace.

         g.       The parties will work together to develop appropriate pricing
                  so that neither party undercuts one another in the
                  marketplace.

         h.       The Marketing Agreement cannot be assigned or transferred
                  without the prior written consent of Summus, Ltd., which
                  consent will not be unreasonably withheld. Notwithstanding the
                  foregoing, the Marketing Agreement can be assigned to an
                  entity capable of performing under the Marketing Agreement


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                  that is not a direct competitor of Summus, Ltd. if Summus,
                  Ltd. receives a nonrefundable cash payment of the greater of
                  (i) $10 Million or (ii) 15% of the prior year's royalties paid
                  under the Marketing Agreement.

         i.       Net Solutions will pay $3,000,000 for this Marketing
                  Agreement. The $3,000,000 will be paid by Net Solutions in
                  installments of $750,000 over four months with the first
                  installment due upon the execution of the Marketing Agreement
                  and each remaining installment due at the end of each
                  successive one month period thereafter. The Marketing
                  Agreement will not be effective until the first $750,000
                  payment is made. Except for the first payment, with respect to
                  these payments, there is a thirty day cure period before the
                  Marketing Agreement terminates, but interest at 8% per annum
                  will accrue on any late payments. The $3 Million advance
                  payment is only recoverable from or against the royalties as
                  specified in Section 2b hereof.

         j.       Except as specifically enlarged herein, the Marketing
                  Agreement shall also contain the Marketing Rights granted in
                  the Brad Richdale Agreement dated March 2, 1998, but Brad
                  Richdale and/or his designee Brad Richdale Direct or Net
                  Solutions shall be relieved of the advertising requirements
                  contained in the Brad Richdale Agreement.

         k.       Except with respect to the video streaming product, there will
                  be no first refusal rights. With respect to any new product,
                  including, but not limited to, a chip, that directly or
                  indirectly suppliants, replaces, competes with, is similar to
                  in its function or intended use, or obsoletes the video
                  streaming product defined in the Marketing Agreement, New
                  Solutions will have first refusal rights to fund the
                  development, and such funding will include the right to market
                  the new product on an exclusive basis, on terms and conditions
                  mutually agreed upon by Summus Ltd. and Net Solutions through
                  reasonable good faith negotiations.

         Notwithstanding anything contained in this section two, if the
         Marketing Agreement is not executed with two weeks of this agreement,
         for whatever reason, then Brad Richdale will personally lend an
         additional $150,000 in cash in immediately available funds to Summus
         Ltd. on the first day of the third week following the execution of this
         agreement. The terms of this note will be the same as the terms
         contained in the note referred in Section 1, except for the dollar
         amount.

3.       Except for the payments contemplated by this agreement, Summus, Ltd.
         will agree to compensate individuals (to initially include Brad
         Richdale, Michael Cimino, and Mike Pruitt) for equity capital invested
         in Summus Ltd. on terms agreeable to Summus Ltd., such compensation in
         accordance with the following formula: 5% on


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         1st Million, 4% on 2nd Million, 3% on 3rd Million, 2% on 4th Million,
         and 1% on all amounts over $4 Million.

4.       Summus Technologies shall, unequivocally, and with all due speed merge
         with Summus, Ltd. (or a merger subsidiary thereof) structured to be tax
         free, on appropriate terms and conditions, once the Marketing Agreement
         has been executed and Summus, Ltd. has obtained the first two $750,000
         payments under the Marketing Agreement in accordance with section 2i.
         Brad Richdale (or his designee) and Cale Yarborough will receive the
         same percentage ownership in Summus, Ltd. as they respectively own in
         Summus Technologies. It is anticipated that prior to the merger Summus,
         Ltd. will be redomiciled in Delaware. In the meantime, Brad Richdale
         agrees that we should move forward with the steps pertaining to the
         Florida operations of Summus Technologies as outlined in our fax dated
         January 5, 1999. Following the merger, Brad Richdale and a designee
         (Michael Cimino) will serve on a seven member board as Class One
         members of a classified board, whereby Class One Directors will have a
         three year term. If the Board is increased, Brad Richdale will retain
         the equivalent of 18% (rounded up) representation on the Board.

5.       Within one year from the execution of this agreement, Net Solutions
         agrees to deliver a $2.5 Million factorable Purchase Order that is
         satisfactory to Summus, Ltd. for products of Summus, Ltd. the
         specifications of which will be mutually agreed upon by you and Summus,
         Ltd. Upon your execution of this agreement, you will receive common
         shares of Summus Technologies equal to 3% of the issued and outstanding
         common shares of Summus Technologies. Upon delivery of the purchase
         order to Summus Ltd. and its acceptance, which will not be unreasonably
         withheld, by Bjorn Jawerth, as the President of Summus, Ltd., you will
         receive additional common shares of Summus Technologies up to 6% of the
         issued and outstanding common shares of Summus Technologies as cash is
         received for the purchase of products under the Purchase Order at a
         rate of 1% per $277,777.78. If the above referenced nine (%) percent is
         not issued, then Brad Richdale (and his designees) specifically do not
         waive any rights they now may have with respect to their existing
         ownership claim thereto.

Brad, I think these are terms that are mutually beneficial to both Summus, Ltd.,
you and to Net Solutions and hopefully these will help make the Summus companies
a success. If you agree to the foregoing, I would appreciate your signing where
indicated below and returning this executed agreement to me. At that time, I
would appreciate your forwarding to Summus, Ltd. the $250,000, at which time
this Agreement will become effective.


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                                                  Sincerely,


                                                    /s/ Bjorn Jawerth
                                                  -------------------------
                                                  Dr. Bjorn Jawerth
                                                  President
                                                  Summus, Ltd.
                                                  Summus Technologies, Inc.

Agreed and Accepted:



/s/ Brad Richdale
------------------------------------------------
Brad Richdale, as it applies to him individually

/s/ Michael M. Cimino               1/14/99
------------------------------------------------
Michael Cimino, President, Zzap.net, Inc. (to be renamed High-Speed Net
Solutions Inc.)


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