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                                                                   EXHIBIT 10.29
                                                                   -------------

                          [incuVest L.P. Letterhead]



AXCESS Inc
December 26, 2000
3208 Commander Drive
Carrollton, Texas 75006


            Re:   Demand Note dated September 14, 2000, executed by AXCESS Inc.
                  (the "Company") payable to incuVest LLC. ("incuVest") (the
                  "Note")

Ladies and Gentlemen:

     incuVest and the Company hereby desire to amend the Note such that
$3,300,000 of the outstanding principal balance of the Note shall be convertible
into Series 2000 Non-Voting Preferred Stock.

     1.   Amendment to Note; Conversion of Debt. incuVest and the Company hereby
          --------------------------------------
agree to amend the Note by permitting incuVest to convert $3,300,000 of the
outstanding principal balance of the Note into shares of the Company's Series
2000 Non-Voting Preferred Stock. The certificates of Designations, Preferences,
Powers and Rights of the Series 2000 Non-Voting Preferred Stock is attached
hereto as Exhibit "A." Accordingly incuVest hereby elects to convert $3,300,000
of the Note into 330 shares of the Series 2000 Non-Voting Preferred Stock (the
"Series 2000 Shares"). Subject to Section 3 below, the Company hereby consents
to the conversion and agrees to issue those shares to incuVest.

     2.   Securities Act Legend; Registration Rights.
          ------------------------------------------

          2.1  The Series 2000 Shares (hereinafter collectively, the "Shares")
will not be registered under the Securities Act of 1933, as amended (the
"Securities Act"). Certificates representing the Shares shall bear a restrictive
legend substantially to the effect of the following:

     THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
     SECURITIES ACT OF 1933, OR APPLICABLE STATE SECURITIES LAWS, OR THE
     SECURITIES LAWS OF ANY OTHER JUSRISDICTION. THEY MAY NOT BE SOLD OR
     TRANSFERRED IN THE ABSENSE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER
     THOSE SECURITIES LAWS OR PURSUANT TO AN EXEMPTION THEREFROM. ADDITIONAL
     RESTRICTIONS REGARDING THE TERMS UNDER WHICH THE SHARES REPRESENTED BY THIS
     CERTIFICATE MAY BE CONVERTED INTO VOTING OR NON-VOTING COMMON STOCK OF THE
     COMPANY, AS THE CASE MAY BE, ARE SET FORTH IN THE RESPECTIVE CERTIFICATES
     OF DESIGNATIONS, PREFERENCES, POWERS AND RIGHTS FOR THE SHARES.

     3.   Representations and Warranties by the Company. The Company hereby
          ---------------------------------------------
represents and warrants to incuVest as follows:

          3.1  The Company is a corporation duly organized, validly existing and
in good standing under the laws of the state of Delaware, and has the corporate
power and authority to execute and deliver this agreement, to issue the Shares
on the basis described herein and otherwise to perform its obligations under
this agreement.
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          3.2  The execution and delivery by the Company of this letter
agreement, the issuance of the Shares, and the performance by the Company of its
obligations hereunder, have been duly authorized by all requisite corporation
action on the part of the Company and will not (a) violate any provision of law,
statute, rule or regulation or any order of any court or other agency of
government, (b) conflict with or violate the Certificate of Incorporation or By-
Laws of the Company, in each case as amended, or (c) violate, conflict with or
constitute (with due notice or lapse of time or both) a default under any
indenture, mortgage, lease, license, agreement or other contract or instrument
or result in the creation or imposition of any lien, charge or encumbrance of
any nature upon the properties or assets of the Company or any of its
subsidiaries, in each case if such violation, conflict, default, lien, charge or
encumbrance would have a material adverse effect on the Company.

          3.3  This letter has been duly executed and delivered by the Company
and constitutes the valid and legally binding obligation of the Company,
enforceable in accordance with its terms, except to the extent the
enforceability hereof may be limited by applicable bankruptcy, moratorium or
similar laws affecting the rights of creditors generally.

          3.4  Based in part upon the representations and warranties of incuVest
by, any federal, state or other governmental department, commission, board,
bureau, agency, or instrumentality or any third party is or will be necessary
for the execution and delivery of this agreement by the Company and the issuance
of the Shares hereunder, other that the filing of a notice of sale on Form D
with the Securities and Exchange Commission in accordance with the rules and
regulations thereof under the Securities Act.

          3.5  The Shares are duly authorized, validly issued, fully paid and
non-assessable shares of Series 2000 Non-Voting Preferred Stock and are not
subject to any preemptive rights.

4.   Representations and Warranties of incuVest. incuVest hereby represents and
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warrants to the Company as follows:

          4.1  incuVest is acquiring the Shares for its own account, for
investment and not with a view to the distribution thereof within the meaning of
the Securities Act.

          4.2  incuVest understands that the Shares have not been registered
under the Securities Act, by reason of their issuance by the Company in
transactions exempt from the registration requirements of the Securities Act,
and that the Shares must be held by incuVest indefinitely unless a subsequent
disposition thereof is registered under the Securities Act or is exempt from
such registration.

          4.3  incuVest further understands that the exemption from registration
afforded by Rule 144 (the provisions of which are known to it) promulgated under
the Securities Act depends on the satisfaction of various conditions, and that,
if applicable, Rule 144 may afford the basis for sales only in limited amounts,
after compliance with the holding periods and other provisions thereof.

          4.4  incuVest understands that its investment hereunder involves
substantial risks and represents and warrants that it has made such independent
examinations and investigations of the Company as it has deemed necessary in
making its investment decision, and incuVest further represents and warrants
that it has had sufficient access to the officers, directors, books and records
of the Company as it has deemed necessary to conduct such examination and
investigation and make such investment decision.

          4.5  incuVest is able to bear the economic risk of the investment
contemplated by this agreement and has such knowledge and experience in
financial and business matters that it is capable of evaluating the merits and
risks of the investment contemplated by this agreement.

5.   Miscellaneous.
     --------------
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          5.1  This letter agreement constitutes our entire agreement with
respect to the subject matter hereof. This letter agreement may not be modified
or amended of any provision hereof waived except by an instrument in writing
signed by the Company and incuVest.

          5.2  This letter agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors and permitted
assigns. The rights of incuVest hereunder shall be assignable to any other
holder of the Shares. Except as provided in the immediately preceding sentence,
this agreement and the rights of incuVest hereunder shall not be assignable, and
any purported assignment hereof or thereof shall be void.

          5.3  This letter agreement may be executed in any number of
counterparts and on separate counterparts, each of which shall be an original
instrument, but all of which together shall constitute a single agreement. One
or more signature pages from any counterpart of this letter agreement may be
attached to any other counterpart of this letter agreement without in any way
changing the effect thereof. This letter agreement shall be effective when
executed and delivered by the Company and incuVest.

          5.4  All notices, requests, demands, consents, waivers, or other
communications made hereunder to any party or holder of Shares shall be in
writing and shall be deemed to have been duly given if delivered personally or
sent by nationally-recognized overnight courier, facsimile or by first class
registered or certified mail, return receipt requested, postage prepaid,
addressed to such party at the address set forth below:

          if to the Company, to the Company address
          first set forth above,:

          with a copy to:

          Haynes and Boone, LLP
          901 Main Street, Suite #3100
          Dallas, Texas 75202-3789
          Attention: William Kleinman; and
          if to incuVest, to incuVest at its address
          first set forth above,

or to such other address as the party to whom such communication is to be given
may have furnished to the other party in writing in accordance herewith. All
such notices, requests, demands, consents, waivers or other communications shall
be deemed to have been delivered (a) in the case of personal delivery, on the
date of delivery, (b) if sent by facsimile, on the date sender receives a
confirmation receipt, (c) if sent by overnight courier, on the next business day
following the date sent and (d) in the case of mailing, on the third business
day following such mailing.

          5.5  All representations, warranties and agreements contained herein
shall survive the execution and delivery of this Agreement and the Sale of the
Shares hereunder.
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         If the foregoing correctly sets forth your understanding of our
agreement, please so indicate by signing and returning the enclosed counterpart
of this letter agreement.

                                        Very truly yours,
                                        incuVest L.P.

                                        By:  incuVest LLC.


                                        By: /s/  Robert J. Bertoldi
                                            ---------------------------------
                                            Robert Bertoldi, President

The undersigned agrees with and
Accepts the foregoing terms and provisions
As of the date first above written

AXCESS INC.


By: /s/  James R. Craig
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   James R. Craig, Chief Financial Officer and Secretary