EXHIBIT 4.8

THIS PROMISSORY NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR
UNDER ANY STATE SECURITIES LAWS. THIS PROMISSORY NOTE MAY NOT BE OFFERED, SOLD,
TRANSFERRED, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF REGISTRATION, OR THE
AVAILABILITY OF AN EXEMPTION FROM REGISTRATION, UNDER THE SECURITIES ACT OF 1933
AND APPROPRIATE STATE SECURITIES LAWS. FURTHERMORE, NO OFFER, SALE, TRANSFER,
PLEDGE OR HYPOTHECATION IS TO TAKE PLACE UNLESS THE MAKER RECEIVES, AT THE
HOLDER'S EXPENSE, AN OPINION OF COUNSEL SATISFACTORY TO THE MAKER TO THE EFFECT
THAT SUCH TRANSFER MAY BE EFFECTED WITHOUT VIOLATING ANY SECURITIES LAWS.


                                  NUCLEUS, INC.

                                 PROMISSORY NOTE

$________________                                                 March 9, 2000


     FOR VALUE RECEIVED, Nucleus, Inc., a Nevada corporation, having its
principal business office at 401 North Michigan Avenue, Chicago, Illinois 60611
(the "Company"), promises to pay to the order of ________________ with an
address at _______________ (said payee together with any successor holder of
this promissory note is referred to herein as "Payee"), the principal sum of
_______________ ($__________) in lawful money of the United States of America on
July 6, 2000 (the "Maturity Date"), provided that the Maturity Date may be
extended to not later than November 3, 2000 at the option of the Company upon
delivery of written notice of such extension to the Payee by not later than
October 27, 2000 and payment of the Extension Fee (defined below) to Payee. This
Note shall bear interest on the principal balance outstanding from time to at
the rate of twelve percent (12%) per annum, such interest payable monthly in
cash on the twentieth day of each month, commencing April 20, 2000, on the terms
and conditions hereinafter set forth. The principal amount of this Note,
together with accrued interest thereon, shall be payable on the Maturity Date
(as the same may be extended) out of any funds of the Company legally available
therefor. The principal amount of this Note, together with accrued interested
thereon, may, at the sole option of the Payee, be converted into shares of
Company common stock, par value $.001 per share (the "Common Stock") on or prior
to the Maturity Date (as the same may be extended), as provided in Section 5 of
this Note. Interest on this Note shall be calculated on the basis of a 365-day
year and the actual number of days elapsed.

     1.   The principal sum, interest thereon and all sums due hereunder shall
be payable at the address of Payee set forth in the heading hereof or at such
other place as Payee, from time to time, may designate in writing.

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     2.   Subject to the Payee's conversion rights set forth in Section 5
below, the Company shall prepay the principal sum hereof and accrued interest
hereon in whole prior to the Maturity Date (as the same may be extended) from
proceeds received by the Company through any public or private offering of any
Common Stock, preferred stock or notes which are convertible into or exercisable
for shares of Common Stock (collectively, "Equity Capital") subsequent to the
date hereof.

     3.   This Note is one of the duly authorized promissory notes of the
Company issued pursuant to the Securities Purchase Agreement dated as of March
1, 2000 (herein referred to as the "Securities Purchase Agreement") by and
between the Company and the Purchasers thereof pursuant to which the Company has
issued promissory notes in the aggregate principal amount of not more than $6.2
million (this Note together with such other promissory notes are collectively
referred to as the "Senior Bridge Notes").

     4.   If the Company elects to extend the original July 6, 2000 Maturity
Date of this Note to a later Maturity Date up to and including November 3, 2000,
the Company shall pay to Payee in consideration therefor (the "Extension Fee")
such number of shares of Common Stock as shall equal five percent (5%) of the
outstanding principal balance of this Note divided by the average closing bid
prices of the Common Stock, as traded on the Nasdaq OTC Bulletin Board, the
Nasdaq Small Cap Market, the Nasdaq National Market or any other national
securities exchange (as the case may be), for the twenty-one (21) consecutive
Trading Days (the "21-Day Average Stock Price") immediately prior to November 3,
2000. As used herein, the term "Trading Days" shall mean the days on which the
New York Stock Exchange, Inc. and the Nasdaq Stock Market, Inc. shall be open
for trading.

     5.   (a)  If the Company seeks to raise any additional Equity Capital, the
     Payee shall have the option to convert this Note at the closing of any such
     Equity Capital financing into a number of whole shares of Common Stock
     which shall equal the outstanding principal amount of this Note plus
     accrued interest thereon (the "Conversion Amount") divided by the price per
     share at which Common Stock is sold in such Equity Capital financing or the
     conversion price of any notes or preferred stock sold in such Equity
     Capital financing. The Company shall give the Payee not less than thirty
     (30) days prior notice of any proposed Equity Capital financing, and copies
     of all offering documents. The Payee may condition his or her conversion of
     this Note upon completion of the Equity Capital financing.

          (b)  In the case of any (1) consolidation or merger of the
     Company into any entity (other than a consolidation or merger that does not
     result in any reclassification, conversion, exchange or cancellation of
     outstanding shares of Common Stock), (2) sale, transfer, lease or
     conveyance of all or substantially all of the assets of the Company as an
     entirety or substantially as an entirety, or (3) reclassification, capital
     reorganization or change of the Common Stock (other than solely a change in
     par value, or from par value to no par value), in each case as a result of
     which shares of Common Stock shall be converted into the right to receive
     stock, securities or other property (including cash or any combination
     thereof), the Payee shall have the option to convert this Note at the
     closing of such event into the kind and amount of securities, cash and
     other property receivable by a holder of the number of shares

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<PAGE>

     of Common Stock into which this Note would have been converted immediately
     prior to such event based upon the Conversion Amount divided by the price
     per share of Common Stock upon which the transaction was valued or is to be
     consummated.

          (c)  Within ten (10) days of receipt of notice of an Event of
     Default (as defined in Section 6 hereof) and prior to any action taken by
     Payee under Section 7 hereof, the Payee shall have the option to convert
     this Note into a whole number of shares of Common Stock equal to the
     Conversion Amount divided by the 21-Day Average Stock Price immediately
     prior to the date of the Event of Default.

          (d)  The Payee may exercise his conversion right, in whole or
     in part, upon surrender of this Note to the Company at its address in the
     heading hereof. Upon surrender thereof, the Company will cause to be issued
     certificates for the total number of shares of Common Stock for which the
     Note is being exercised as are required for delivery, within fifteen (15)
     days of such exercise, to the Payee.

          (e)  No fractional shares of Common Stock shall be issued by in
     connection with any conversion of this Note and no cash payment shall be
     made therefor.

     6.   The occurrence of any of the following shall constitute an Event of
Default hereunder:

          (a)  The failure of the Company to pay when due the principal sum
     hereof or any accrued interest hereon.

          (b)  The commencement of any involuntary case or the filing of
     a petition against the Company seeking reorganization, arrangement,
     adjustment or composition of or in respect of the Company under the Federal
     bankruptcy laws, as now or hereafter constituted, or under any other
     applicable Federal or state bankruptcy, insolvency, reorganization or other
     similar law, or seeking the appointment of a receiver, liquidator,
     custodian, trustee (or similar official) of the Company for any substantial
     part of its property, or seeking the winding-up or liquidation of its
     affairs (and such involuntary case or petition is not dismissed within
     sixty (60) days after the filing thereof), or the commencement by the
     Company of a voluntary case or the institution by the Company of
     proceedings to be adjudicated a bankrupt or insolvent, or proceedings
     against it, under the Federal bankruptcy laws as now or hereafter
     constituted, or any other applicable Federal or state bankruptcy or
     insolvency or other similar law, or the consent by the Company to the
     appointment of or taking possession by a receiver, liquidator, trustee,
     custodian (or other similar official) of the Company for any substantial
     part of its property, or the making by it of any assignment for the benefit
     of creditors or the admission by it in writing of its inability to pay its
     debts generally as they become due.

          (c)  The occurrence of an Event of Default under any Senior
     Bridge Notes issued by the Company pursuant to the Securities Purchase
     Agreement.

          (d)  The breach by the Company of any representation or warranty
     contained in the Securities Purchase Agreement.

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<PAGE>

          (e)  The failure by the Company to perform any covenant or
     agreement on its part required to be performed under this Note, the Senior
     Bridge Notes, the Securities Purchase Agreement or the Registration Rights
     Agreement unless such covenant or agreement shall be fully performed within
     ten (10) days after notice of default.

          (f)  The Company shall sell or otherwise dispose of all or
     substantially all of its assets or consummate a merger, consolidation or
     reorganization with or into one or more other entities, except for any such
     transaction in which the holders of shares of capital stock of the Company
     on the date hereof, directly or indirectly, continue to own a majority of
     the voting securities of the surviving entity having the right under
     ordinary circumstances to elect a majority of the Board of Directors or
     comparable governing body of such entity.

          (g)  The Company shall issue any debt obligation senior in
     right of payment or security to the Senior Bridge Notes.

     7.   If there shall occur an Event of Default described in Paragraph 6
hereof, Payee may at his option, by written notice to the Company, declare the
entire unpaid balance of principal with interest accrued thereon and all other
sums due under this Note to be immediately due and payable. If there shall occur
an Event of Default described in subparagraph 6(b), the entire unpaid balance of
principal with interest accrued thereon and all other sums due under this Note
shall be immediately due and payable without notice to the Company. If there
shall occur an Event of Default, Payee shall be entitled to costs of collection,
including reasonable attorneys' fees.

     8.   The Company hereby waives presentment for payment, demand, notice of
demand, notice of nonpayment or dishonor, protest and notice of protest of this
Note, and all other notices in connection with the delivery, acceptance,
performance, default, or enforcement of the payment of this Note. The Company
agrees that its liability shall be unconditional, without regard to the
liability of any other party, and shall not be affected in any manner by any
indulgence, extension of time, renewal, waiver or modification granted or
consented to by Payee.

     9.   This Note and the obligations of the Company shall be senior in
right of payment to all other debt obligations of the Company (other than Senior
Bridge Notes) arising or incurred subsequent to the date of this Note except for
senior or secured debt obligations assumed by the Company in connection with the
acquisition or purchase of other entities or assets by merger or otherwise.

     10.  All rights and remedies of Payee under this Note and any applicable
law are separate and cumulative, and the exercise of one shall not limit or
prejudice the exercise of any other such rights or remedies. No delay or
omission by Payee in exercising any right or remedy shall operate as a waiver
thereof. No waiver of any rights and remedies hereunder, and no modification or
amendment of this Note, shall be deemed made by Payee unless in writing and duly
signed by Payee. Any such written waiver shall apply only to the particular
instance specified therein and shall not impair the further exercise of such
right or remedy or of any other right or remedy of Payee, and no

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<PAGE>

single or partial exercise of any right or remedy under this Note shall preclude
any other or further exercise thereof or any other right or remedy.

     11.  The shares of Common Stock into which this Note is convertible in
accordance with Section 5 hereof are subject to the rights and privileges set
forth in the Registration Rights Agreement of even date herewith among the
Company and the Senior Bridge Note investors.

     12.  The Company and Payee agree that this Note shall be governed by and
construed according to the laws of the State of Illinois applicable to contracts
wholly performed within such jurisdiction.

     13.  ANY LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER, OR IN
CONNECTION WITH THIS NOTE, SHALL BE BROUGHT AND MAINTAINED EXCLUSIVELY IN THE
COURTS OF THE STATE OF ILLINOIS OR IN THE UNITED STATES DISTRICT COURT FOR THE
NORTHERN DISTRICT OF ILLINOIS. EACH OF THE COMPANY AND PAYEE HEREBY EXPRESSLY
AND IRREVOCABLY SUBMITS TO THE JURISDICTION OF THE COURTS OF THE STATE OF
ILLINOIS AND OF THE UNITED STATES DISTRICT COURT FOR THE NORTHERN DISTRICT OF
ILLINOIS FOR THE PURPOSE OF ANY SUCH LITIGATION AS SET FORTH ABOVE. EACH OF THE
COMPANY AND PAYEE FURTHER IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS BY
REGISTERED MAIL, POSTAGE PREPAID, OR BY PERSONAL SERVICE WITHIN OR WITHOUT THE
STATE OF ILLINOIS. EACH OF THE COMPANY AND PAYEE HEREBY EXPRESSLY AND
IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY OBJECTION WHICH
IT MAY NOW OR HEREAFTER HAVE TO THE LAYING OF VENUE OF ANY SUCH LITIGATION
BROUGHT IN ANY SUCH COURT REFERRED TO ABOVE AND ANY CLAIM THAT ANY SUCH
LITIGATION HAS BEEN BROUGHT IN AN INCONVENIENT FORUM.

     14.  EACH OF THE COMPANY AND PAYEE HEREBY WAIVES ANY RIGHT TO A TRIAL BY
JURY IN ANY ACTION OR PROCEEDING TO ENFORCE OR DEFEND ANY RIGHTS UNDER THIS
NOTE, AND AGREES THAT ANY SUCH ACTION OR PROCEEDING SHALL BE TRIED BEFORE A
COURT AND NOT BEFORE A JURY.

     15.  All notices and other communications provided for under this Note
shall be made in writing to the addresses (either of which may be changed by
written notice) of the Company and Payee at their respective addresses in the
heading hereof. Notices shall be deemed to have been duly given when delivered
by hand, or, if mailed, three business days after deposit in the mail, postage
prepaid and return receipt requested.

     16.  This Note may be amended by an instrument in writing executed by
the Company and the Payees who hold a majority of the aggregate principal amount
of the Senior Bridge Notes and any such amendment shall be binding on all Payees
of the Senior Bridge Notes; provided, however, that no such amendment that
alters the principal amount hereof, the rate of interest payable hereon the
Maturity Date of this Note or the provisions of Section 5 hereof shall be
binding on any Payee without the prior written consent of such Payee.

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<PAGE>

     17.  This Note shall be binding upon and shall inure to the benefit of
the Company, Payee and their respective successors, assigns, personal
representatives, heirs or legatees, as the case may be.

                            [SIGNATURE ON NEXT PAGE]

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<PAGE>

     IN WITNESS WHEREOF, the undersigned has executed this Note the day and
year first above written.


                                                  NUCLEUS, INC.


                                              By:______________________________
                                                 Its___________________________

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