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                                                                   Exhibit 10.17

THIS NOTE AND THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS
(THE "ACTS"). THEY MAY NOT BE SOLD, OFFERED FOR SALE, TRANSFERRED, PLEDGED,
HYPOTHECATED OR OTHERWISE DISPOSED OF WITHOUT A REGISTRATION STATEMENT IN EFFECT
WITH RESPECT TO THE ACTS OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO
BORROWER THAT SUCH REGISTRATION IS NOT REQUIRED.

                           CONVERTIBLE PROMISSORY NOTE

$2,000,000                                                        APRIL __, 2001

         FOR VALUE RECEIVED, LEARN2.COM, INC., a Delaware corporation having its
principal executive offices at 1311 Mamaroneck Avenue, Suite 210, White Plains,
New York 10605 ("Borrower") hereby promises to pay to the order of E-STAMP
CORPORATION, a Delaware corporation having its principal executive offices at
2051 Stierlin Court, Mountain View, California 94043 ("Holder"), the principal
sum of TWO MILLION DOLLARS ($2,000,000) and, together with such amount, all
interest accrued hereunder as provided herein. This Convertible Promissory Note
is hereinafter referred to as this "Note".

         1. LOAN AND TERMS OF PAYMENT.

                  1.1 THE LOAN. Borrower acknowledges indebtedness to Holder in
the amount of Two Million Dollars ($2,000,000) (the "Loan").

                  1.2 INTEREST. The Loan shall accrue interest from the date
hereof until the Loan is paid in full at a rate equal to ten percent (10%) per
annum (based on a three hundred and sixty five (365) day year).

                  1.3 PRINCIPAL AND INTEREST REPAYMENT. Subject to the
provisions of Sections 2 and 4 hereof, the principal amount of this Note,
together with accrued and unpaid interest thereon, shall be due and payable on
April 30, 2002 (the "Maturity Date"). Subject to the provisions of Section 4
hereof, no payment of interest shall be made until the Maturity Date.

                  1.4 PARI PASSU. Subject to the Security Agreement, this Note
shall rank pari passu with and equal in right with the indebtedness of Borrower
pursuant to that certain 6% Convertible Debenture, dated March 10, 2000 (the
"RGC Indebtedness"), issued to RGC International Investors, LDC in the aggregate
principal amount of $10,000,000.

                  1.5 FORM OF PAYMENT. Both the principal amount of this Note,
and all interest accrued thereon, shall be paid in such currency of the United
States of America as shall be legal tender at the time of payment, and all
payments or prepayments of principal and interest and other sums due pursuant to
this Note shall be made by certified check to Holder at its address set forth
above, or in immediately available funds by wire transfer to Holder's account at
such bank as Holder shall have previously designated to Borrower. When any date
on which principal and interest are due and payable falls on a Saturday, Sunday
or legal holiday, then such payment shall be due and
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payable on the first business day immediately following such date and interest
shall be payable at the rate set forth herein for the period of such extension.

                  1.6 OPTIONAL PREPAYMENT. Subject to earlier conversion
pursuant to Section 2, this Note may be prepaid by Borrower, in whole or in
part, at any time or from time to time, without premium or penalty, upon thirty
(30) days' prior written notice by Borrower to Holder. All prepayments made on
this Note shall be applied first to the payment of all unpaid interest accrued
on this Note, and then to the outstanding and unpaid principal amount of this
Note as of the date of the payment.

         2. CONVERSION.

                  2.1 RIGHTS, PRIVILEGES AND PREFERENCES. The Series E Stock
shall have the rights, privileges and preferences set forth in ANNEX A hereto.

                  2.2 RIGHT OF CONVERSION. Subject to and in compliance with the
provisions of this Section 2, Holder may, at its option and at any time, convert
all, or any portion of, the principal amount of this Note, together with accrued
and unpaid interest thereon, into shares of Series E Convertible Preferred Stock
of Borrower (the "Series E Stock") at a per share conversion price equal to
$1000. In the event that Holder desires to convert this Note into shares of
Series E Stock, Holder shall surrender this Note at the office of Borrower and
shall give written notice to Borrower at such office that it elects to convert
the same. Thereupon, Borrower shall promptly issue and deliver to Holder a
certificate or certificates for the number of shares of Series E Stock to which
Holder is entitled. Such conversion shall be deemed to have been made at the
close of business on the date of such surrender of this Note and notice, and the
person entitled to receive the shares of Series E Stock issuable upon such
conversion shall be treated for all purposes as the record holder of such shares
of Series E Stock on such date.

         3. COVENANTS OF BORROWER.

                  3.1 LIMITATIONS ON ADDITIONAL INDEBTEDNESS. So long as
Borrower shall have any obligation under this Note, Borrower shall not, without
the Holder's written consent, create, incur, assume or suffer to exist any
liability for borrowed money, except (a) borrowings in existence or committed on
the date hereof, (b) indebtedness to trade creditors incurred in the ordinary
course of business, (c) borrowings, the proceeds of which shall be used to repay
this Note, or (d) asset based borrowings involving accounts receivable or
inventory financing or leaseholds.

                  3.2 RESERVATION OF SERIES E STOCK. So long as Borrower shall
have any obligation under this Note, Borrower shall reserve from its authorized
but unissued Preferred Stock a sufficient number of shares of Series E Stock to
provide for the issuance of Series E Stock upon the conversion of this Note and
shall reserve from its authorized and unissued Common Stock a sufficient number
of shares to provide for the issuance of Common Stock issuable upon conversion
of those shares of Series E Stock.

                  3.3 NASDAQ APPROVAL. If the issuance of the Series E Stock
pursuant to the provisions of Section 2 above would require approval of
Borrower's stockholders, or the Nasdaq


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Stock Market or other governmental or regulatory authority, Borrower shall
promptly make such filings and take such other actions as are necessary or
advisable to obtain such approval or an exemption therefrom. Pending such
approval or exemption therefrom, Holder may nonetheless convert that portion of
this Note that is then convertible into the maximum number of shares of Series E
Stock permitted by applicable law and the applicable rules and regulations of
the National Stock Market.

                  3.4 NOTIFICATION OF EVENTS OF DEFAULT. Borrower shall
immediately notify Borrower of the occurrence of an Event of Default described
in subsection 4.1 below.

         4. EVENTS OF DEFAULT.

                  4.1 DEFINITION OF EVENT OF DEFAULT. Any one or more of the
following events shall constitute an Event of Default:

                           (a) Borrower fails to pay on the due date any
principal or interest on this Note, or any other amount due under this Note,
when and as the same shall become due and payable, whether at the due date
thereof or at the date fixed for prepayment thereof or by acceleration thereof
or otherwise, and such default shall continue unremedied for a period of five
(5) business days;

                           (b) Borrower fails to perform or observe any other
covenant or agreement contained in this Note to be performed by it, and such
breach is not cured or such failure continues for a period of ten (10) business
days after receipt of written notice by Borrower from the Holder stating that
such notice is notice of an Event of Default.

                           (c) A default or event of default shall have occurred
with respect to the RGC Indebtedness, which default shall not have been waived
or cured within any applicable grace period provided in the RGC Indebtedness,
and which results in the acceleration of the maturity date thereof;

                           (d) An involuntary proceeding shall be commenced or
an involuntary petition shall be filed in a court of competent jurisdiction
seeking (i) relief in respect of Borrower, or of a substantial part of the
property or assets of Borrower, under Title 11 of the United States Code, as now
constituted or hereafter amended, or any other federal, state or foreign
bankruptcy, insolvency, receivership or similar law, (ii) the appointment of a
receiver, trustee, custodian, sequestrator, conservator or similar official for
Borrower or for a substantial part of the property or assets of Borrower or
(iii) the winding-up or liquidation of Borrower, and any such proceeding or
petition shall continue undismissed for sixty (60) days or an order or decree
approving or ordering any of the foregoing shall be entered;

                           (e) Borrower shall (i) voluntarily commence any
proceeding or file any petition seeking relief under Title 11 of the United
States Code, as now constituted or hereafter amended, or any other federal,
state or foreign bankruptcy, insolvency, receivership or similar law, (ii)
consent to the institution of, or fail to contest in a timely and appropriate
manner, any proceeding or the filing of any petition described in (d) above,
(iii) apply for or consent to the appointment of a receiver, trustee, custodian,
sequestrator, conservator or similar official for Borrower or for a


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substantial part of the property or assets of Borrower, (iv) file an answer
admitting the material allegations of a petition filed against it in any such
proceeding, (v) make a general assignment for the benefit of creditors, (vi)
become unable, admit in writing its inability or fail generally to pay its debts
as and when they become due or (vii) take any action for the purpose of
effecting any of the foregoing;

                           (f) The Board of Directors of Borrower shall have
withdrawn, modified or changed in a manner adverse to Holder its approval or
recommendation of the Agreement and Plan of Merger between Borrower and Holder
dated April 19, 2001 (the "Merger Agreement") or the merger of Borrower and
Holder (the "Merger"), or shall have recommended an Acquisition Proposal (as
defined in the Merger Agreement) relating to Borrower with a person other than
Holder;

                           (g) Borrower shall have executed an agreement in
principle or definitive agreement relating to an Acquisition Proposal (as
defined in the Merger Agreement) relating to Borrower with a person other than
Holder; or

                           (h) Borrower shall have breached any representation,
warranty, covenant or other agreement contained in the Merger Agreement, which
breach results in a Material Adverse Effect (as defined in the Merger Agreement)
on Borrower and cannot be or has not been cured within fifteen (15) days after
the giving of written notice by Holder to Borrower, and which results in
Holder's termination of the Merger Agreement.

                  4.2 RIGHTS UPON EVENT OF DEFAULT. Upon the occurrence of any
Event of Default, Holder, at its option, may declare the entire principal amount
of this Note then outstanding, together with accrued and unpaid interest
thereon, (i) immediately due and payable in the event of any Event of Default
other than an Event of Default described in subsection 4.1(h) above, or (ii) due
and payable sixty days after the termination of the Merger Agreement upon the
occurrence of an Event of Default described in subsection 4.1(h), in each case
without presentment, demand, protest or notice or other formality of any kind;
provided that, upon the occurrence of an Event of Default described in
subsections 4.1(d) and (e) above, this Note shall automatically become due and
payable without presentment, demand, protest or notice or other formality of any
kind.

                  4.3 OTHER REMEDIES. If any Event of Default has occurred and
is continuing, irrespective of whether this Note has become or has been declared
immediately due and payable under Section 4.2, the Holder may proceed to protect
and enforce its rights by an action at law, suit in equity or other appropriate
proceeding, whether for the specific performance of any agreement contained
herein, or for an injunction against a violation of any of the terms hereof or
thereof, or in aid of the exercise of any power granted hereby or thereby or by
law or otherwise.

         5. RESTRICTIONS ON TRANSFER.

                  This Note and the Series E Stock issuable upon conversion
hereof shall not be transferable prior to the termination of the Merger
Agreement.

         6. MISCELLANEOUS.


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                  6.1 UNCONDITIONAL OBLIGATION; WAIVERS. The obligations of
Borrower to make the payments provided for in this Note are absolute and
unconditional and not subject to any defense, set-off, counterclaim, rescission,
recoupment or adjustment whatsoever. Borrower hereby waives presentment and
demand for payment, notice of non-payment, notice of dishonor, protest, notice
of protest, bringing of suit and diligence in taking any action to collect any
amount called for under this Note, and shall be directly and primarily liable
for the payment of all amounts owing and to be owing hereon, regardless of and
without any notice, diligence, act or omission with respect to the collection of
any amount called for hereunder. No waiver of any provision of this Note shall
be effective unless in writing, signed by Holder, and a waiver of any one
provision shall not constitute a waiver of any other terms hereof, or otherwise
release or discharge the liability of Borrower under this Note. No failure to
exercise and no delay in exercising, on the part of Holder, any right, power or
privilege under this Note shall operate as a waiver thereof nor shall partial
exercise of any right, power or privilege. The rights and remedies herein
provided are cumulative and are not exclusive of any rights or remedies provided
by law.

                  6.2 NOTICES AND ADDRESSES. Any notice, demand, request,
waiver, or other communication under this Note shall be in writing and shall be
deemed to have been duly given on the date of service, if personally served or
sent by telecopy; on the business day after notice is delivered to a courier or
mailed by express mail, if sent by courier delivery service or express mail for
next day delivery; and on the third day after mailing, if mailed to the party to
whom notice is to be given, by first class mail, registered, return receipt
requested, postage prepaid and addressed as follows:


                 To Borrower:               Learn2.com, Inc.
                                            1311 Mamaroneck Avenue, Suite 210
                                            Mamaroneck, New York 10605
                                            Fax: (914) 682-4440
                                            Attention: President

                 with a copy to:            Swidler Berlin Shereff Friedman, LLP
                                            The Chrysler Building
                                            405 Lexington Avenue
                                            New York, New York 10174
                                            Fax: (212) 891-9598
                                            Attention: Gerald Adler, Esq.

                 To Holder:                 E-Stamp Corporation
                                            2051 Stierlin Court
                                            Mountain View, California 94043
                                            Fax: (650) 919-7533
                                            Attention: President

                 with a copy to:            Wilson Sonsini Goodrich & Rosati
                                            650 Page Mill Road
                                            Palo Alto, California 94304-1050
                                            Fax: (650) 493-6811


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                                            Attention: N. Anthony Jeffries, Esq.

                  6.3 LOST, STOLEN OR MUTILATED NOTE. Upon receipt by Borrower
of evidence satisfactory to it of the loss, theft, destruction or mutilation of
this Note or any Note exchanged for it, and (in the case of loss, theft or
destruction) of unsecured indemnity satisfactory to it, and upon reimbursement
to Borrower of all reasonable expenses incidental thereto, and upon surrender
and cancellation of such Note, if mutilated, Borrower will make and deliver in
lieu of such Note a new Note of like tenor and unpaid principal amount and dated
as of the original date of this Note.

                  6.4 SEVERABILITY; BINDING EFFECT. Any provision of this Note
which is invalid or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such invalidity or
unenforceability without rendering invalid or unenforceable the remaining terms
and provisions of this Note or affecting the validity or unenforceability of any
of the terms and provisions of this Note in any other jurisdiction. This Note
shall be binding upon and inure to the benefit of the parties hereto and their
successors and assigns.

                  6.5 EXPENSES. If any action is instituted to collect this
Note, Borrower promises to pay all costs and expenses, including without
limitation, reasonable attorneys' fees and costs, incurred in connection with
such action.

                  6.6 USURY. Anything in this Note to the contrary
notwithstanding, it is expressly stipulated and agreed that the intent of
Borrower and the Holder is to comply at all times with all usury and other laws
relating to this Note. If the laws of the State of Delaware or any other
jurisdiction would now or hereafter render usurious, or are revised, repealed or
judicially interpreted, so as to render usurious, the indebtedness evidenced by
this Note, then it is the Borrower's and the Holder's express intent that all
excess amounts theretofore collected by the Holder be credited to the principal
balance of this Note (or, if the Note has been paid in full, refunded to the
Borrower), and the provisions of this Note immediately be deemed reformed and
the amounts therefor collectible hereunder reduced, without the necessity of
execution of any new document, so as to comply with the then applicable law, but
so as to permit the recovery of the fullest amount otherwise called for
hereunder.

                  6.7 GOVERNING LAW. This Note shall be construed in accordance
with, and governed by, the laws of the State of Delaware without regard to
principles of conflicts of law.

                  6.8 AMENDMENTS. This Note cannot be changed orally or
terminated orally. Any amendment of, or supplement to or other modification of
this Note must be in a written instrument executed by both parties hereto.

                  6.9 SECTION HEADINGS. Section headings herein have been
inserted for reference only and shall not be deemed to limit or otherwise
affect, in any matter, or be deemed to interpret in whole or in part any of the
terms or provisions of this Note.


                     [THIS SPACE INTENTIONALLY LEFT BLANK.]


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         IN WITNESS WHEREOF, this Note has been executed and delivered as of the
date specified above.


                                        LEARN2.COM, INC.


                                        By:
                                           -------------------------------------


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


                                        Title:
                                              ----------------------------------