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                                                                    EXHIBIT 10.8

                                 MERCATA, INC.

                             SUBSCRIPTION AGREEMENT


     1.   Subscription.  In connection with an offering (the "Offering") of
Common Stock (the "Common Stock") of Mercata, Inc. (the "Company"), the
purchaser whose name appears on the signature page of this Agreement
("Purchaser"), hereby subscribes for four million (4,000,000) shares (the
"Shares") at a price of ten cents ($0.10) per share.

     2.   Payment.  Purchaser encloses herewith its check payable to the Company
in the amount equal to the total purchase price of the shares indicated in
section 1 above.

     3.   Representations and Warranties of the Purchaser.  The Purchaser hereby
represents and warrants that:

          3.1  Requisite Power and Authority.  Purchaser has all necessary power
and authority under all applicable provisions of law to execute and deliver this
Agreement and to carry out its provisions.  All action on Purchaser's part
required for the lawful execution and delivery of this Agreement have been or
will be effectively taken prior to the closing of the Offering.  Upon their
execution and delivery, this Agreement will be a valid and binding obligation of
Purchaser, enforceable in accordance with their terms, except (a) as limited by
applicable bankruptcy, insolvency, reorganization, moratorium or other laws of
general application affecting enforcement of creditors' rights, and (b) general
principles of equity that restrict the availability of equitable remedies.

          3.2  Investment Representations.  Purchaser understands that the
Shares have not been registered under the Securities Act of 1933, as amended
(the "Act").  Purchaser also understands that the Shares are being offered and
sold pursuant to an exemption from registration contained in the Act based in
part upon Purchaser's representations contained in the Agreement.  Purchaser
hereby represents and warrants as follows:

               (a)  Acquisition Entirely for Own Account. Purchaser is acquiring
the Shares for Purchaser's own account for investment only, not as a nominee or
agent, and not with a view to the resale or distribution of any part thereof,
and Purchaser has no present intention of selling, granting any participation
in, or otherwise distributing the same. By executing this Agreement, the
Purchaser further represents that the Purchaser does not have any contract,
undertaking, agreement or arrangement with any person to sell, transfer or grant
participation to such person or to any third person, with respect to any of the
Shares.

               (b)  Disclosure of Information.  Purchaser has received all the
information it considers necessary or appropriate for deciding whether to
purchase the Shares. The Purchaser further represents that it has had an
opportunity to discuss the Company's business, management and financial affairs
with the Company and to ask questions and receive answers from the Company
regarding the terms and conditions of the offering of the Shares.

               (c)  Purchaser Can Protect Its Interest and Bear Economic Risk.
Purchaser has such knowledge and experience in financial and business matters
that it is capable

                                       1.
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of evaluating the merits and risks of the investment in the Company and has the
capacity to protect its own interest in connection with the transactions
contemplated in this Agreement. Purchaser understands that it must bear the
economic risk of this investment indefinitely unless the Shares are registered
pursuant to the Act, or an exemption from registration is available. Purchaser
understands that the Company has no present intention of registering the Shares
or any shares of its Common Stock. Purchaser also understands that there is no
assurance that any exemption from registration under the Act will be available
and that, even if available, such exemption may not allow Purchaser to transfer
all or any portion of the Shares under the circumstances, in the amounts or at
the times Purchaser might propose. Further, Purchaser is aware of no publication
of any advertisement in connection with the transactions contemplated in this
Agreement. Purchaser also represents it has not been organized for the purpose
of acquiring the Shares.

               (d)  Accredited Purchaser. Purchaser is an accredited purchaser
within the meaning of Regulation D under the Act.

               (e)  Restricted Securities. Purchaser understands that the Shares
may not be sold, transferred, or otherwise disposed of without registration
under the Act or an exemption therefrom, and that in the absence of an effective
registration statement covering the Shares or an available exemption from
registration under the Act, the Shares must be held indefinitely. In particular,
each Purchaser is aware of the provisions of Rule 144 promulgated under the Act
that the Shares may not be sold pursuant to Rule 144 unless all of the
conditions of that Rule are met. Among the conditions for use of Rule 144 may be
the availability of certain current information to the public about the Company.
Such information is not now available and the Company has no present plans to
make such information available.

          3.3  Transfer Restrictions.  Purchaser acknowledges and agrees that
the Shares are subject to restrictions on transfer.

     4.   Counterparts.  This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

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     5.   Entire Agreement.  This Agreement constitutes the full and entire
understanding and agreement between the parties with regard to the subjects
hereof and no party shall be liable or bound to any other in any manner by any
representations, warranties, covenants and agreements except as specifically set
forth herein and therein.

                                      Purchaser:


4,000,000                             By: /s/ Paul G. Allen
-----------------------                   -------------------------
Number of Shares
                                      Name: Paul G. Allen
                                            -----------------------

                                      Address:_____________________

$400,000                                      _____________________
-----------------------                       _____________________
Amount of Investment
($0.10 per Share)


     The foregoing Agreement is hereby confirmed and accepted by the Company as
of October 7, 1998.

                                      Mercata, Inc.


                                      By /s/ Jon C. Engman
                                         --------------------------------------

                                      Name: Jon C. Engman
                                            -----------------------------------

                                      Title: Vice President & Treasurer
                                             ----------------------------------

                                      Address: 110 - 110th Ave. NE, Suite 390
                                              ---------------------------------

                                                Bellevue, WA 98004
                                              ---------------------------------



                                       3.