<PAGE>
                                  Exhibit 4.28

      NEITHER THIS WARRANT NOR THE SHARES OF STOCK ISSUABLE UPON EXERCISE HEREOF
      HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR
      STATE SECURITIES LAWS. NO SALE, TRANSFER OR OTHER DISPOSITION OF THIS
      WARRANT OR SAID SHARES MAY BE EFFECTED WITHOUT (i) AN EFFECTIVE
      REGISTRATION STATEMENT RELATED THERETO UNDER APPLICABLE SECURITIES LAWS,
      OR (ii) AN EXEMPTION FROM REGISTRATION UNDER SUCH LAWS IS AVAILABLE.


Warrant No.             STOCK PURCHASE WARRANT           No. of Shares 1,950,000
-----------                                              -----------------------

                  To Subscribe for and Purchase Common Stock of
                   AFFINITY INTERNATIONAL TRAVEL SYSTEMS, INC.

      THIS CERTIFIES that, for value received, SCHOEMANN VENTURE CAPITAL, L.L.C.
(together with any subsequent transferees of all or any portion of this Warrant,
the "Holder"), is entitled, upon the terms and subject to the conditions
hereinafter set forth, to subscribe for and purchase from AFFINITY INTERNATIONAL
TRAVEL SYSTEMS, INC., a Nevada corporation (hereinafter called the "Company"),
at the price hereinafter set forth in Section 2, up to 1,950,000 fully paid and
non-assessable shares (the "Shares") of the Company's Common Stock, $0.001 par
value per share (the "Common Stock").

      1. Definitions. As used herein the following term shall have the following
meaning:

      "Act" means the Securities Act of 1933, as amended, or a successor statute
thereto and the rules and regulations of the Securities and Exchange Commission
issued under that Act, as they each may, from time to time, be in effect.

      2. Purchase Rights. The purchase rights represented by this Warrant shall
be exercisable by the Holder in whole or in part commencing on date hereof. The
purchase rights represented by this Warrant shall expire five (5) years from the
date hereof. This Warrant may be exercised for Shares at a price of twenty-five
cents (US$0.25) per share, subject to adjustment as provided in Section 6 (the
"Warrant Purchase Price").

      3. Exercise of Warrant. Subject to Section 2 above and the further
provisions of this Section 3, the purchase rights represented by this Warrant
may be exercised, in whole or in part and from time to time, by the surrender of
this Warrant and the duly executed Notice of Exercise (the form of which is
attached as Exhibit A) at the principal office of the Company and by the payment
to the Company, by check, of an amount equal to the Warrant Purchase Price per
share multiplied by the number of Shares then being purchased or via "cashless
exercise" as provided hereinafter. Upon exercise, the Holder shall be entitled
to receive, within a reasonable time, but in no event later than ten (10)
business days from the date of exercise, a

<PAGE>

certificate or certificates, issued in the Holder's name or in such name or
names as the Holder may direct, for the number of Shares so purchased. The
Shares so purchased shall be deemed to be issued as of the close of business on
the date on which this Warrant shall have been exercised.

      The Company has agreed, and does hereby covenant to, use its best faith
efforts to have all of the Shares registered under the Act such that upon
exercise of this warrant, the Holder shall receive the Shares free from any and
all restrictions on transfer or sale, including, but not limited to,
restrictions imposed by Rule 144 under the Securities Act of 1933, as amended.
If a registration statement pertaining to the Shares is not declared effective
by the United States Securities and Exchange Commission ("SEC") by June 20,
2000, at any time thereafter, the warrant holder, whether the undersigned or
otherwise, in lieu of any cash payment required hereunder, shall have the right
to exercise the warrants in whole or in part by surrendering the warrants in
exchange for the number of shares of the Company's common stock equal to (x) the
number of shares as to which the warrants are being exercised multiplied by (y)
a fraction, the numerator of which is the Market Price (as defined below) of the
common stock less the exercise price of the warrants being exercised, and the
denominator of which is such Market Price. The term "Market Price" means the
average of the closing sale price per share of the common stock on the principal
stock exchange or market on which the common stock is then quoted or traded on
each of the ten (10) consecutive trading days preceding the date on which
written notice of election to exercise the warrants has been given to the
Company (a "cashless exercise"). If the warrant holder opts for a cashless
exercise of the warrants, no other consideration shall be paid to the Company,
other than surrendering the warrant itself, nor will there be paid any
commission or other remuneration to any other person or entity by the warrant
holder. In the event that the warrant holder is not permitted to "tack" the
holding period of the warrants to the holding period of the common stock
received upon the cashless exercise for purposes of satisfaction of the holding
period requirements of Rules 144(d)(3)(ii) and 144(k) under the Securities Act
of 1933, as amended, for whatever reason and there is no presently filed
registration statement effective as to the shares received or to be received
through the cashless exercise of this Warrant, the Company shall, upon receipt
of the written request of the warrant holder, promptly prepare and file a
registration statement with the SEC with respect to all of the shares underlying
this warrants.

      4. Shares to be Issued; Reservation of Shares. The Company covenants that
the Shares that may be issued upon the exercise of the purchase rights
represented by this Warrant will, upon issuance in accordance herewith, be fully
paid and non-assessable, and free from all liens and charges with respect to the
issue thereof. During the period within which the purchase rights represented by
the Warrant may be exercised, the Company will at all times have authorized and
reserved, for the purpose of issuance upon exercise of the purchase rights
represented by this Warrant, a sufficient number of shares of its Common Stock
to provide for the exercise of the right represented by this Warrant.

      5. No Fractional Shares. No fractional shares shall be issued upon the
exercise of this Warrant. In lieu thereof, a cash payment shall be made equal to
such fraction multiplied by


                                      -2-
<PAGE>

the fair market value of such shares of Common Stock, as determined in good
faith by the Company's Board of Directors.

      6. Adjustments of Warrant Purchase Price and Number of Shares. If there
shall be any change in the Common Stock of the Company through merger,
consolidation, reorganization, recapitalization, stock dividend, stock split or
other change in the corporate structure of the Company, appropriate adjustments
shall be made by the Board of Directors of the Company (or if the Company is not
the surviving corporation in any such transaction, the Board of Directors of the
surviving corporation) in the aggregate number and kind of shares subject to
this Warrant, and the number and kind of shares and the price per share then
applicable to shares covered by the unexercised portion of this Warrant.

      7. No Rights as Shareholders. This Warrant does not entitle the Holder to
any voting rights or other rights as a shareholder of the Company prior to
exercise of this Warrant and the payment for the Shares so purchased.
Notwithstanding the foregoing, the Company agrees to transmit to the Holder such
information, documents and reports as are generally distributed to holders of
the capital stock of the Company concurrently with the distribution thereof to
the shareholders. Upon valid exercise of this Warrant and payment for the Shares
so purchased in accordance with the terms of the Warrant, the Holder or the
Holder's designee, as the case may be, shall be deemed a shareholder of the
Company.

      8. Sale or Transfer of the Warrant and the Shares; Legend. The Warrant and
the Shares shall not be sold or transferred unless either (i) they first shall
have been registered under applicable securities laws, or (ii) such sale or
transfer is exempt from the registration requirements of such laws. Each
certificate representing any Warrant shall bear the legend set out on page 1
hereof. Each certificate representing any Shares shall bear a legend
substantially in the following form, as appropriate:

      THE SHARES EVIDENCED HEREBY HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH
      A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO
      SUCH SALE OR DISTRIBUTION MAY BE EFFECTED WITHOUT AN EFFECTIVE
      REGISTRATION STATEMENT RELATED THERETO UNDER APPLICABLE SECURITIES LAWS OR
      PURSUANT TO AN EXEMPTION UNDER APPLICABLE SECURITIES LAWS.

      The Warrant and Shares may be subject to additional restrictions on
transfer imposed under applicable state and federal securities law.

      9. Modifications and Waivers. This Warrant may not be changed, waived,
discharged or terminated except by an instrument in writing signed by the party
against which enforcement of the same is sought.

      10. Notices. Any notice, request or other document required or permitted
to be given or delivered to the Holder or the Company shall be delivered, or
shall be sent by certified or registered mail, postage prepaid, to the Holder at
its address shown on the books of the


                                      -3-
<PAGE>

Company or in the case of the Company, at the address indicated therefor on the
signature page of this Warrant, or, if different, at the principal office of the
Company.

      11. Loss, Theft, Destruction or Mutilation of Warrant. The Company
covenants with the Holder that upon its receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant or any stock certificate and, in the case of any such loss, theft
or destruction, of an indemnity or security reasonably satisfactory to it, and
upon reimbursement to the Company of all reasonable expenses incidental thereto,
and upon surrender and cancellation of this Warrant or stock certificate, if
mutilated, the Company will make and deliver a new Warrant or stock certificate,
of like tenor, in lieu of the lost, stolen, destroyed or mutilated Warrant or
stock certificate.

      12. Binding Effect on Successors. This Warrant shall be binding upon any
corporation succeeding the Company by merger, consolidation or acquisition of
all or substantially all of the Company's assets, and all of the obligations of
the Company relating to the Shares issuable upon exercise of this Warrant shall
survive the exercise and termination of this Warrant and all of the covenants
and agreements of the Company shall inure to the benefit of the successors and
assigns of the Holder.

      13. Governing Law. This Warrant shall be construed and enforced in
accordance with, and the rights of the parties shall be governed by, the laws of
the State of Nevada.

      IN WITNESS WHEREOF, AFFINITY INTERNATIONAL TRAVEL SYSTEMS, INC. has caused
this Warrant to be executed by its officer thereunto duly authorized.

ORIGINAL ISSUANCE EFFECTIVE AS OF: December 20, 1999.

                      AFFINITY INTERNATIONAL TRAVEL SYSTEMS, INC.


                      /s/ D.G. Brandano
                      -----------------------------------------
                      By: Daniel G. Brandano, President

                      Address: Affinity International Travel Systems, Inc.
                               100 Second Avenue South, Suite 1100 South
                               St. Petersburg, FL 33701


                                      -4-
<PAGE>

                                    EXHIBIT A


                               NOTICE OF EXERCISE


      To: AFFINITY INTERNATIONAL TRAVEL SYSTEMS, INC.

      1. The undersigned hereby elects to purchase _________ shares of Common
Stock of AFFINITY INTERNATIONAL TRAVEL SYSTEMS, INC. pursuant to the terms of
the attached Warrant, and tenders herewith payment of the purchase price of such
shares in full.

      2. Please issue a certificate or certificates representing said shares in
the name of the undersigned or in such other name or names as are specified
below.

      3. The undersigned represents that the aforesaid shares of Common Stock
are being acquired for the account of the undersigned for investment and not
with a view to, or for resale in connection with, the distribution thereof and
that the undersigned has no present intention of distributing or reselling such
shares. The undersigned further represents that such shares shall not be sold or
transferred unless either (1) they first shall have been registered under
applicable securities laws or (ii) or an exemption from applicable registration
requirements is available.

      4. In the event of partial exercise, please re-issue an appropriate
Warrant exercisable into the remaining shares.


                                          -------------------------------
                                          Name:

                                          Address:
                                                  -----------------------

                                                  -----------------------

                                                  -----------------------

                                          -------------------------------
                                          (Signature)

                                          -------------------------------
                                          (Date)


                                      -5-