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                                                                    EXHIBIT 4.21


THE WARRANT AND THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT (THE
"SECURITIES") HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE
"SECURITIES ACT") OR UNDER ANY STATE SECURITIES OR BLUE SKY LAWS ("BLUE SKY
LAWS"). NO TRANSFER, SALE, ASSIGNMENT, PLEDGE, HYPOTHECATION OR OTHER
DISPOSITION OF THIS WARRANT OR THE SECURITIES OR ANY INTEREST THEREIN MAY BE
MADE EXCEPT (A) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE
SECURITIES ACT AND ANY APPLICABLE BLUE SKY LAWS OR (B) IF THE COMPANY HAS BEEN
FURNISHED WITH BOTH AN OPINION OF COUNSEL FOR THE HOLDER, WHICH OPINION AND
COUNSEL SHALL BE REASONABLY SATISFACTORY TO THE COMPANY, TO THE EFFECT THAT NO
REGISTRATION IS REQUIRED BECAUSE OF THE AVAILABILITY OF AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT AND APPLICABLE BLUE SKY LAWS, AND
ASSURANCES THAT THE TRANSFER, SALE, ASSIGNMENT, PLEDGE, HYPOTHECATION OR OTHER
DISPOSITION WILL BE MADE ONLY IN COMPLIANCE WITH THE CONDITIONS OF ANY SUCH
REGISTRATION OR EXEMPTION.

                   WARRANT TO PURCHASE SHARES OF COMMON STOCK
                              OF POPMAIL.COM, INC.

WARRANT NO. WT-1                                          Bloomington, Minnesota
                                                                December 1, 1999

         This certifies that, for value received, WAYNE L. TEIDGE, or his
successors or assigns ("Holder") is entitled to purchase from PopMail.com, inc.
(the "Company") Twenty Thousand (20,000) fully paid and nonassessable shares
(the "Shares") of the Company's Common Stock, $.01 par value (the "Common
Stock"), at any time and from time to time from the date hereof until December
1, 2004 (the "Warrant Exercise Period"), at an exercise price of $1.625 per
share (the "Exercise Price"), subject to adjustment as herein provided.

         This Warrant is subject to the following provisions, terms and
conditions:

         1.   Exercise of Warrant. The rights represented by this Warrant may be
exercised by the Holder, in whole or in part (but not as to a fractional share
of Common Stock), by the surrender of this Warrant (properly endorsed, if
required, at the Company's principal office in Bloomington, Minnesota, or such
other office or agency of the Company as the Company may designate by notice in
writing to the Holder at the address of such Holder appearing on the books of
the Company at any time within the period above named), and upon payment to it
by certified check, bank draft or cash of the purchase price for such Shares.
The Company agrees that the Shares so purchased shall have and are deemed to be
issued to the Holder as the record owner of such Shares as of the close of
business on the date on which this Warrant shall have been surrendered and
payment made for such Shares as aforesaid. Certificates for the Shares of Common
Stock so purchased shall be delivered to the Holder within a reasonable time,
not exceeding ten (10) days, after the rights represented by this Warrant shall
have been so exercised, and, unless this Warrant has expired, a new Warrant
representing the number of Shares, if any, with respect to which this Warrant
shall not then have been exercised shall also be delivered to the Holder within
such time. The Company may require that any such new Warrant or any certificate
for Shares purchased upon the exercise hereof bear a legend substantially
similar to that which is contained on the face of this Warrant.

         2.   Transferability of this Warrant. This Warrant is issued upon the
following terms, to which each Holder consents and agrees:

              a.   Until this Warrant is transferred on the books of the
         Company, the Company will treat the Holder of this Warrant registered
         as such on the books of the Company as the absolute owner hereof for
         all purposes without being affected by any notice to the contrary.


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              b.   This Warrant may not be exercised, and this Warrant and the
         Shares underlying this Warrant shall not be transferable, except in
         compliance with all applicable state and federal securities laws,
         regulations and orders, and with all other applicable laws, regulations
         and orders.

              c.   Prior to making any disposition of this Warrant or of any
         of the Shares underlying this Warrant, the Holder will give written
         notice to the Company describing the manner of any such proposed
         disposition. The Warrant may not be transferred, and the Shares may not
         be transferred, without the Holder obtaining an opinion of counsel
         satisfactory in form and substance to the Company's counsel stating
         that the proposed transaction will not result in a prohibited
         transaction under the Securities Act, and applicable Blue Sky laws. By
         accepting this Warrant, the Holder agrees to act in accordance with any
         conditions reasonably imposed on such transfer by such opinion of
         counsel.

              d.   Neither this issuance of this Warrant nor the issuance of
         the Shares underlying this Warrant have been registered under the
         Securities Act.

         3.   Certain Covenants of the Company. The Company covenants and agrees
that all Shares which may be issued upon the exercise of the rights represented
by this Warrant, upon issuance and full payment for the Shares so purchased,
will be duly authorized and issued, fully paid and nonassessable and free from
all taxes, liens and charges with respect to the issue hereof, except those that
may be created by or imposed upon the Holder or its property, and without
limiting the generality of the foregoing, the Company covenants and agrees that
it will from time to time take all such actions as may be requisite to assure
that the par value per share of the Common Stock is at all times equal to or
less than the effective purchase price per share of the Common Stock issuable
pursuant to this Warrant. The Company further covenants and agrees that during
the period within which the rights represented by this Warrant may be exercised,
the Company will at all times have authorized and reserved free of preemptive or
other rights for the exclusive purpose of issue upon exercise of the purchase
rights evidenced by this Warrant, a sufficient number of shares of its Common
Stock to provide for the exercise of the rights represented by this Warrant.

         4.   Adjustment of Exercise Price and Number of Shares. The Exercise
Price and number of Shares are subject to the following adjustments:

              a.   Adjustment of Exercise Price for Stock Dividend, Stock
Split or Stock Combination. In the event that (i) any dividends on any class of
stock of the Company payable in Common Stock or securities convertible into or
exercisable for Common Stock ("Common Stock Equivalents") shall be paid by the
Company, (ii) the Company shall subdivide its then outstanding shares of Common
Stock into a greater number of shares, or (iii) the Company shall combine its
outstanding shares of Common Stock, by reclassification or otherwise, then, in
any such event, the Exercise Price in effect immediately prior to such event
shall (until adjusted again pursuant hereto) be adjusted immediately after such
event to a price (calculated to the nearest full cent) determined by dividing
(a) the number of shares of Common Stock outstanding immediately prior to such
event, multiplied by the then existing Exercise Price, by (b) the total number
of shares of Common Stock outstanding immediately after such event, and the
resulting quotient shall be the adjusted Exercise Price per share. No adjustment
of the Exercise Price shall be made if the amount of such adjustment shall be
less than $.05 per share, but in such case any adjustment that would otherwise
be required then to be made shall be carried forward and shall be made at the
time and together with the next subsequent adjustment which, together with any
adjustment or adjustments so carried forward, shall amount to not less than $.05
per share.


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              b.   Adjustment of Number of Shares Purchasable on Exercise of
Warrants. Upon each adjustment of the Exercise Price pursuant to this Section,
the Holder shall thereafter (until another such adjustment) be entitled to
purchase at the adjusted Exercise Price the number of shares, calculated to the
nearest full share, obtained by multiplying the number of shares specified in
such Warrant (as adjusted as a result of all adjustments in the Exercise Price
in effect prior to such adjustment) by the Exercise Price in effect prior to
such adjustment and dividing the product so obtained by the adjusted Exercise
Price.

              c.   Notice as to Adjustment. Upon any adjustment of the
Exercise Price and any increase or decrease in the number of shares of Common
Stock purchasable upon the exercise of the Warrant, then, and in each such case,
the Company within thirty (30) days thereafter shall give written notice
thereof, by first class mail, postage prepaid, addressed to each Holder as shown
on the books of the Company, which notice shall state the adjusted Exercise
Price and the increased or decreased number of shares purchasable upon the
exercise of the Warrants, and shall set forth in reasonable detail the method of
calculation and the facts upon which such calculation is based.

              d.   Effect of Reorganization, Reclassification, Merger, etc. If
at any time while any Warrant is outstanding there should be any capital
reorganization of the capital stock of the Company (other than the issuance of
any shares of Common Stock in subdivision of outstanding shares of Common Stock
by reclassification or otherwise and other than a combination of shares provided
for in Section 4(a) hereof), or any consolidation or merger of the Company with
another corporation, or any sale, conveyance, lease or other transfer by the
Company of all or substantially all of its property to any other corporation,
which is effected in such a manner that the holders of Common Stock shall be
entitled to receive cash, stock, securities, or assets with respect to or in
exchange for Common Stock, then, as a part of such transaction, lawful provision
shall be made so that each Holder shall have the right thereafter to receive,
upon the exercise hereof, the number of shares of stock or other securities or
property of the Company, or of the successor corporation resulting from such
consolidation or merger, or of the corporation to which the property of the
Company has been sold, conveyed, leased or otherwise transferred, as the case
may be, which the Holder would have been entitled to receive upon such capital
reorganization, reclassification of capital stock, consolidation, merger, sale,
conveyance, lease or other transfer, if such Warrant had been exercised
immediately prior to such capital reorganization, reclassification of capital
stock, consolidation, merger, sale, conveyance, lease or other transfer. In any
such case, appropriate adjustments (as determined by the Board of Directors of
the Company) shall be made in the application of the provisions set forth in
this Warrant (including the adjustment of the Exercise Price and the number of
Shares issuable upon the exercise of the Warrants) to the end that the
provisions set forth herein shall thereafter be applicable, as near as
reasonably may be, in relation to any shares or other property thereafter
deliverable upon the exercise of the Warrants as if the Warrants had been
exercised immediately prior to such capital reorganization, reclassification of
capital stock, such consolidation, merger, sale, conveyance, lease or other
transfer and the Warrant Holders had carried out the terms of the exchange as
provided for by such capital reorganization, consolidation or merger. The
Company shall not effect any such capital reorganization, consolidation, merger
or transfer unless, upon or prior to the consummation thereof, the successor
corporation or the corporation to which the property of the Company has been
sold, conveyed, leased or otherwise transferred shall assume by written
instrument the obligation to deliver to each Holder such shares of stock,
securities, cash or property as in accordance with the foregoing provisions such
Holder shall be entitled to purchase.

         5.   No Rights as Stockholders. This Warrant shall not entitle the
Holder as such to any voting rights or other rights as a stockholder of the
Company.


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         6.   Registration Rights. If at any time during the Warrant Exercise
Period, the Company shall propose to file any registration statement (other than
any registration on Form S-4, S-8 or any other similarly inappropriate form, or
any successor forms thereto) (the "Registration Statement") under the 1933 Act
covering a public offering of the Company's Common Stock, it will notify the
Holder hereof at least thirty (30) days prior to each such filing and will use
its best efforts to include in the Registration Statement (to the extent
permitted by applicable regulation), the Common Stock purchased or purchasable
by the Holder upon the exercise of the Warrant to the extent requested by the
Holder hereof within twenty (20) days after receipt of notice of such filing
(which request shall specify the interest in this Warrant or the Shares intended
to be sold or disposed of by such Holder and describe the nature of any proposed
sale or other disposition thereof); provided, however, that if a greater number
of Common Stock is offered for participation in the proposed offering than in
the reasonable opinion of the managing underwriter of the proposed offering can
be accommodated without adversely affecting the proposed offering, then the
amount of Shares proposed to be offered by such Holders for registration, as
well as the number of securities of any other selling shareholders participating
in the registration, shall be proportionately reduced to a number deemed
satisfactory by the managing underwriter. The Company shall bear all expenses
and fees incurred in connection with the preparation, filing, and amendment of
the Registration Statement with the Commission, except that the Holder shall pay
all fees, disbursements and expenses of any counsel or expert retained by the
Holder and all underwriting discounts and commissions, filing fees and any
transfer or other taxes relating to the Shares included in the Registration
Statement. The Holder of this Warrant agrees to cooperate with the Company in
the preparation and filing of any Registration Statement, and in the furnishing
of information concerning the Holder for inclusion therein, or in any efforts by
the Company to establish that the proposed sale is exempt under the 1933 Act as
to any proposed distribution.

         7.   Governing Law. This Warrant shall be governed by and construed in
accordance with the laws of the State of Minnesota.

         8.   Amendments and Waivers. The provisions of this Warrant may not be
amended, modified or supplemented, and waiver or consents to departures from the
provisions hereof may not be given, unless the Company agrees in writing and has
obtained the written consent of the Holders.

         9.   Notices. All notices or communications hereunder, except as herein
otherwise specifically provided, shall be in writing and if sent to the Holder
shall be mailed, delivered, or telefaxed and confirmed to the Holder at his or
her address set forth on the records of the Company; or if sent to the Company
shall be mailed, delivered, or telefaxed and confirmed to PopMail.com, inc.,
4801 West 81st Street, Suite 112, Bloomington, MN 55437 or to such other address
as the Company or the Holder shall notify the other as provided in this Section.

         IN WITNESS WHEREOF, PopMail.com, inc. has caused this Warrant to be
signed by its duly authorized officer in the date set forth above.

                                                 POPMAIL.COM, INC.

                                                 By:  s/ Thomas W. Orr
                                                    Its:  CFO

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                                SUBSCRIPTION FORM

         To be signed only upon exercise of Warrant.

         The undersigned, the holder of the within Warrant, hereby irrevocably
elects to exercise the purchase right represented by such Warrant for, and to
purchase thereunder,                      of the shares of Common Stock of
PopMail.com, inc. (the "Shares") to which such Warrant relates and herewith
makes payment of $            therefor in cash, certified check or bank draft
and requests that a certificate evidencing the Shares be delivered to,
                               , the address for whom is set forth below the
signature of the undersigned:

Dated:
      -----------------------

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


                                            -----------------------------------
                                            -----------------------------------
                                            (Address)



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                                 ASSIGNMENT FORM

         To be signed only upon authorized transfer of Warrant.

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns, and
transfers unto                                          the right to purchase
shares of Common Stock of PopMail.com, inc. to which the within Warrant relates
and appoints                    attorney, to transfer said right on the books
of                          with full power of substitution in the premises.

Dated:
      -----------------------
                                            -----------------------------------
                                            (Signature)


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                                            -----------------------------------
                                            (Address)


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