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                                                                   Exhibit 10.51


                          HOUSTONSTREET EXCHANGE, INC.

                                SERIES C WARRANT


Exercisable and Expires in                   Right to Purchase 56,132,280
Accordance with the Agreement                shares of Series C Preferred Stock
                                             (subject to adjustment)

No. W-C001

                                    PREAMBLE

         HOUSTONSTREET EXCHANGE, INC. (the "Company"), a Delaware corporation,
hereby certifies that, for value received, BayCorp Holdings, Ltd. ("Holder") is
entitled, subject to the terms set forth below, to purchase from the Company
fully paid and nonassessable shares of Series C Preferred Stock, $0.01 par
value, of the Company, at the purchase price per share (the "Purchase Price") of
the $.15 (the "Initial Purchase Price"). The number and character of such shares
of Series C Preferred Stock and the Purchase Price are subject to adjustment as
provided in Sections 1 and 9 of the Agreement.

         This Warrant is one of the Series C Stock Purchase Warrants (the
"Warrants"), evidencing the right to purchase shares of Series C Preferred Stock
of the Company, issued pursuant to the Warrant Agreement dated as of even date
herewith among the Company and the other parties to the Agreement, a copy of
which is on file at the principal office of the Company. The Warrants evidence
rights to purchase an aggregate of 56,132,280 shares of Series C Preferred Stock
of the Company (the "Shares"), subject to adjustment as provided in Sections 1
and 9 of the Agreement (the adjustment pursuant to Section 1 referring solely to
additional shares of Series C Preferred Stock as may be requested by the Holder
as provided by Section 2 of the Senior Secured Promissory Note issued in favor
of the Holder). Capitalized terms used herein but not defined herein shall have
the meaning set forth in the Series C Preferred Stock Warrant Agreement of even
date herewith.

     1.  Restricted Shares.

         The holder of this Certificate by its acceptance covenants and agrees
that this Warrant and the Shares are Restricted Shares in accordance with
Section 7 of the Agreement, and may only be transferred in accordance with that
section.

     2.  Exercise of Warrant.

         The holder of this Warrant may exercise it in accordance with
paragraphs 1 and 4 of the Agreement.

     3.  Purchase Price and Shares.

         The Purchase Price and number of Shares issuable hereunder may be
adjusted in accordance with Sections 1 and 9 of the Agreement (the adjustment
pursuant to Section 1
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referring solely to additional shares of Series C Preferred Stock as may be
requested by the Holder as provided by Section 2 of the Senior Secured
Promissory Note issued in favor of the Holder).

     4.  The Agreement.

         This Warrant is subject to all other terms of the Agreement.



Dated:  March 30, 2001          HOUSTONSTREET EXCHANGE, INC.

(Corporate Seal)                By: /s/ Frank W. Getman Jr.
                                    -------------------------------------------
                                    Frank W. Getman Jr.
                                    Its President & Chief Executive Officer


Attest: /s/ Cynthia A. Johnson