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                                                                    EXHIBIT 4.20


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. MCP-2                                         Bloomington, Minnesota
                                                                December 1, 1999

         This certifies that, for value received, METROPOLITAN CAPITAL PARTNERS,
INC., or its successors or assigns ("Holder") is entitled to purchase from
PopMail.com, inc. (the "Company") One Hundred Fifty Thousand (150,000) 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, at an exercise price of $1.00 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.

              a.   Exercise for Cash. 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.

              b.   Cashless Exercise. Upon receipt of a notice of cashless
exercise, the Company shall deliver to the Holder (without payment by the Holder
of any exercise price) that number of Shares that is equal to the quotient
obtained by dividing (x) the value of the Warrant on the date that the Warrant
shall have been surrendered (determined by subtracting the aggregate exercise
price for the Shares in effect on the Exercise Date from the aggregate Fair
Market Value (hereinafter defined) for the Shares by (y) the Fair Market Value
of one share of Common Stock. A


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notice of "cashless exercise" shall state the number of Shares as to which the
Warrant is being exercised. "Fair Market Value" for purposes of this Section (b)
shall mean the average of the Common Stock closing prices reported by the
principal exchange on which the Common Stock is traded, or the last sale prices
as reported by the National Association of Securities Dealers, Inc. Automated
Quotation System ("Nasdaq") National Market or SmallCap Market, as the case may
be, for the ten (10) business days immediately preceding the Exercise Date or,
in the event no public market shall exist for the Common Stock at the time of
such cashless exercise, Fair Market Value shall mean the fair market value of
the Common Stock as the same shall be determined in the good faith discretion of
the Board of Directors, after full consideration of all factors then deemed
relevant by such Board in establishing such value, including by way of
illustration and not limitation, the per share purchase price of Common Stock or
per security convertible into one share of Common Stock of the most recent sale
of shares of Common Stock or securities convertible into Common Stock by the
Company after the date hereof all as evidenced by the vote of a majority of the
directors then in office.

         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.

              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 of 1933, as amended ("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


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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.

              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


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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.

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

         7.   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.

         8.   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:
                                               --------------------------------
                                            Its:
                                                -------------------------------

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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:
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                                            [Signature]

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                                            [Printed]

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                                            [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:
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                                            [Signature]

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                                            [Printed]

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                                            [Address]

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