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                                                                     EXHIBIT 4.5


                                 PROMISSORY NOTE





$100,000.00                                                Date:  April 29, 1999


FOR VALUE RECEIVED, CHICAGO MAP CORPORATION, an Illinois corporation
("Borrower"), promises to pay to STEVEN J. PESKAITIS, an individual ("Lender"),
or order, the principal amount of ONE HUNDRED THOUSAND DOLLARS ($100,000.00)
with interest on the unpaid principal balance at one percent (1%) per month (the
"Loan").

This Promissory Note is the Note referred to as Exhibit A to the Interim Loan
Agreement of even date herewith entered into by Borrower and Lender. Pursuant to
the terms of the Interim Loan Agreement, Lender has made the Loan to Borrower as
follows:

1.   Payment and Term. The Loan shall bear interest on the principal balance at
     1% per month from and after the date thereof until payment in full. The
     principal and interest, is due and payable as follows:

(a)     The Note is due in full four (4) months from the date hereof, unless
        extended by Lender pursuant to written notice thereof, or such other
        agreement as may be entered into between Lender and Borrower with
        respect thereto; and

(b)     Borrower may, but is not obligated to, make periodic payments in part or
        full payment of the Loan until due.

2.   Application of Payments. Unless applicable law provides otherwise, all
     payments received by Lender shall be applied by Lender first in payment
     of interest payable and next to the principal.

3.1  Events of Default. Upon the occurrence and during the continuance of
     any one or more events hereinafter enumerated, Lender may forthwith or
     at any time thereafter during the continuance of any such event, by
     notice in writing to Borrower, declare the unpaid balance of the
     principal and interest shall become and shall be immediately due and
     payable without presentation, demand, protest, notice of protest, or
     other notice of dishonor, all of which are hereby expressly waived by
     Borrower, such events being as follows:


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(a)     Default in the payment of the principal and interest of the Note or any
        portion thereof when the same shall become due and payable, whether at
        maturity as therein expressed, by acceleration, or otherwise, unless
        cured within 10 days after notice thereof by the holder of such Note to
        Borrower;

(b)     The creditors under any priority secured indebtedness of Borrower shall
        declare the amounts due thereunder to be due and payable following
        default;

(c)     Default in the due observance or performance of any other covenant or
        obligation contained in the Interim Loan Agreement, this Note or the
        Acquisition Agreement unless observed or performed within 10 days after
        notice thereof to Borrower by lender; provided, if compliance is not
        possible within 10 days, default shall occur upon failure within 10 days
        to take steps that will produce compliance as soon as is reasonably
        practicable;

(d)     Any representation or warranty herein or in the Acquisition Agreement
        made by Borrower proves to have been untrue in any material respects as
        of the date as of which the facts therein set forth were stated or
        certified, and corrective measures, satisfactory to Lender with respect
        as of the date as of which the facts therein set forth were stated or
        certified, and corrective measures, satisfactory to Lender with respect
        thereto shall not have been taken within 10 days after notice thereof to
        Lender; provided, if compliance is not possible within 10 days, default
        shall occur upon failure within 10 days to take steps that will produce
        compliance as is reasonably practicable;

(e)     Borrower shall file a voluntary petition in bankruptcy or a voluntary
        position seeking reorganization, or shall file an answer admitting the
        jurisdiction of the court and any material allegations of an involuntary
        petition filed pursuant to any act of Congress relating to bankruptcy or
        to any act purporting to be amendatory thereof, or shall be adjudicated
        bankrupt, or shall make an assignment for the benefit of creditors, or
        shall apply for or consent to the appointment of any receiver or trustee
        for Borrower, or of all or any substantial portion of its property, or
        Borrower shall make an assignment to an agent authorized to liquidate
        any substantial part of its assets;

(f)     An order shall be entered pursuant to any act of Congress relating to
        bankruptcy or to any act purporting to be amendatory thereof approving
        an involuntary petition seeking reorganization of Borrower, or an order
        of any court shall be entered appointing any receiver or trustee of or
        for Borrower, or any receiver or trustee of all or any substantial
        portion of the property of Borrower, or a writ or warrant of attachment
        or any similar process shall be issued by any court against all or any
        substantial portion of the property of Borrower, and such order
        approving a petition seeking reorganization or appointing a receiver or
        trustee is not vacated or stayed, or such writ, warrant of attachment,
        or similar process is not released or bonded within 60 days after its
        entry or levy; or
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(g)     The rendering against the Borrower of final judgment for the payment of
        money in excess of $25,000 and failure of the Borrower to appeal
        therefrom (or from the order, decree, or process pursuant to which such
        judgment was granted, passed, entered, or affirmed) and obtain a stay of
        execution thereof within the period prescribed by law for appeal, or to
        have such judgment discharged and satisfied within 60 days after the
        expiration of such period or of the period of any such stay, whichever
        shall later occur.

3.2  Procedure on Default.  Upon the occurrence of an event of default,  and at
     any time  thereafter,  Lender may elect to declare the entire Note
     immediately due and payable.

(a)     In the event of default in the payment of said Note when due or declared
        due, Lender shall have all the rights and remedies of a secured party
        and shall be entitled to avail itself of all such other rights and
        remedies that may now or hereafter exist at law or in equity for the
        collection of the Note and the enforcement of the covenants herein and
        the foreclosure of the security interest created hereby and resort to
        any remedy provided hereunder or provided by the Illinois Uniform
        Commercial Code, or by any other law of the state of Illinois, shall not
        prevent the concurrent or subsequent employment of any other appropriate
        remedy or remedies; and

(b)     The requirement of reasonable notice to Borrower of the time and place
        of any public sale of the security or of the time after which any
        private sale, or any other intended disposition thereof is to be made,
        shall be met if such notice is mailed, postage prepaid, to Borrower at
        the address of such party designated below, at least 30 days before the
        date of any public or private sale or other disposition is to be made.

3.3  Defaults Under Prior Indebtedness. Upon the default by Borrower of any
     term, covenant, or condition required to be performed by if on any priority
     secured indebtedness or the receipt by Borrower from any such priority
     secured creditor of notice of any default under such indebtedness, whether
     or not repayment of the indebtedness is accelerated, Borrower shall
     promptly advise Lender in writing of the nature and amount of default and
     of the action, if any, threatened by such priority secured creditor.
     Notwithstanding the Borrower's obligation to cure any and all such
     defaults, Lender may, but shall not be obligated to do so, in the name,
     place, and stead of Borrower and, in the case of such curative efforts by
     Lender, succeed to all of the rights, remedies, and security of such
     priority creditor.

4.   Attorneys' Fees. If this Note is placed with an attorney for collection, or
     is suit be instituted for collection, or is any other remedy permitted by
     law is pursued by Lender, because of any default in the terms and
     conditions herein, then in such event, the undersigned agrees to pay
     reasonable attorneys' fees, costs, and other expenses incurred by Lender in
     so doing.

5.   Governing Law. This Master Note shall be governed by and construed and
     enforced in accordance with the laws of the state of Illinois.

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6.   Security Interest. Borrower shall execute a Security Agreement and an
     Escrow Agreement wherein Borrower shall grant to Lender a security interest
     in the Collateral as defined in the Interim Loan Agreement, sufficient to
     secure the obligation created hereunder, which agreements shall be made a
     part of the Interim Loan Agreement and this Note and incorporated herein by
     this reference.



                                      BORROWER:

                                      CHICAGO MAP CORPORATION, an Illinois
                                      corporation



                                      By: /s/ John B. McLean
                                         -----------------------------------
                                         Its Duly Authorized Representative