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                                                                    Exhibit 10.9

                                 PROMISSORY NOTE

$510,00.00                         Austin, Texas                November 8, 1999

     FOR VALUE RECEIVED, the undersigned, James E. Cahill (the "Maker"), hereby
unconditionally promises to pay to the order of Netpliance, Inc., a Texas
corporation, (the "Payee"), at its offices in Austin, Texas or such other
address given to the Maker by the Payee, the principal sum of Five Hundred Ten
Thousand and No One-Hundredths Dollars ($510,000.00), in lawful money of the
United States of America, together with interest on the unpaid principal balance
from day-to-day remaining, computed from the date hereof until payment in full
of the principal sum at the rate per annum of seven percent (7%).

     1.    Payment. The principal of and interest upon this promissory note (the
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"Note") shall be due and payable on November 8, 2004.

     2.    Application of Payment. Payments made to the Payee by the Maker
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hereunder shall be applied first to accrued and unpaid interest on the principal
amount of this Note and then to the outstanding principal amount of this Note.

     3.    Security Interest. This Note is secured by a security interest
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evidenced by that certain Pledge Agreement (the "Pledge Agreement"), dated
November 8, 1999, by and between Maker and Payee.

     4.    Waivers. Maker waives demand for payment, presentment, protest,
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notice of protest and non-payment, or other notice of default, notice of
acceleration and intention to accelerate, and agrees that its liability under
this Note shall not be affected by any renewal or extension in the time of
payment hereof or any other indulgences and hereby consents to any and all
renewals, extensions, indulgences, releases or changes.

     No waiver by Payee of any of its rights or remedies hereunder shall be
considered a waiver of any other or subsequent right or remedy of Payee; no
delay or omission in the exercise or enforcement by Payee of any such rights or
remedies shall be construed as a waiver thereof; and no exercise or enforcement
of any such rights or remedies shall be held to exhaust any such right or
remedy.

     5.    Events of Default. An "event of default" shall exist hereunder if any
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one or more of the following events shall occur and be continuing:

           (a)  the Maker shall fail or refuse to pay when due any principal of,
     or interest upon, this Note when due and payable;

           (b)  the Maker shall (i) apply for or consent to the appointment of a
     receiver, trustee, custodian, intervenor or liquidator of the Maker or of
     all or a substantial part of its assets, (ii) file a voluntary petition in
     bankruptcy, admit in writing that it is unable to pay its debts as they
     become due or generally not pay its debts as they become due, (iii) make a
     general assignment for the benefit of creditors, (iv) file a petition or
     answer seeking reorganization or an arrangement with creditors or to take
     advantage of any bankruptcy or insolvency laws, (v) file an answer
     admitting the material allegations of, or

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     consent to, or default in answering, a petition filed against it in any
     bankruptcy, reorganization or insolvency proceeding, or (vi) take corporate
     action for the purpose of effecting any of the foregoing;

           (c)  an involuntary petition or complaint shall be filed against the
     Maker seeking bankruptcy or reorganization or the appointment of a
     receiver, custodian, trustee, intervenor or liquidator of the Maker, or of
     all or substantially all of its assets, and such petition or complaint
     shall not have been dismissed within thirty (30) days of the filing
     thereof; or an order, order for relief, judgment or decree shall be entered
     by any court of competent jurisdiction or other competent authority
     approving a petition or complaint seeking reorganization of the Maker or
     appointing a receiver, custodian, trustee, intervenor or liquidator of the
     Maker, or of all or substantially all of its assets; or

           (d)  the failure to have discharged within a period of ten (10) days
     after the commencement thereof any attachment, sequestration or similar
     proceedings against any of the Maker's assets.

     6.    Remedies. Upon the occurrence of any Event of Default, the Payee may,
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at its option, declare the entire unpaid balance of principal and accrued
interest on this Note to be immediately due and payable and exercise any and all
remedies permitted by the Pledge Agreement or applicable law, provided, however,
upon the occurrence of any of the Events of Default described in items 5.(b) or
5.(c) above, the entire unpaid balance of principal and accrued interest upon
this Note shall, without any action by the Payee, immediately become due and
payable without demand for payment, presentment, protest, notice of protest and
non-payment, or other notice of default, notice of acceleration and intention to
accelerate or any other notice, all of which are expressly waived by the Maker.

     7.    Prepayments. The Maker may prepay this Note, without penalty, in
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whole or in part, at any time, by giving the Payee written notice of the amount
to be prepaid at least two days prior to the date of prepayment.

     8.    Usury Savings Clause. Any provision herein, in any other document
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securing the payment of this Note, or in any other agreement or commitment
between the Maker and the Payee, whether written or oral, expressed or implied,
to the contrary notwithstanding, the Payee shall never be entitled to charge,
receive, or collect, nor shall amounts received hereunder be credited as
interest so that the Payee shall be paid, a sum greater than interest at the
maximum nonusurious interest rate, if any, that at any time may be contracted
for, charged, received, or collected on the indebtedness evidenced by this Note
under applicable law (the "Maximum Rate"). It is the intention of the parties
that this Note, and all other instruments securing the payment of this Note or
executed or delivered in connection herewith, shall comply with applicable law.
If the Payee ever contracts for, charges, receives, or collects, anything of
value which is deemed to be interest under applicable law, and if the occurrence
of any circumstance or contingency, whether acceleration of maturity of this
Note, delay in advancing proceeds of this Note; or other event, should cause
such interest to exceed interest at the Maximum Rate, any such excess amount
shall be applied to the reduction of the unpaid principal balance of this Note
or any other indebtedness owed to the Payee by the Maker, and if this Note and
such other indebtedness is paid in full, any remaining excess shall be paid to
the Maker. In determining

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whether or not the interest hereon exceeds interest at the Maximum Rate, the
total amount of interest shall be spread throughout the entire term of this Note
until its payment in full in a manner which will cause the interest rate on this
Note not to exceed the Maximum Rate.

     9.  Notice. All notices to be given hereunder shall be in writing and shall
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be deemed given at the earlier of when actually received or three days after
being deposited in the United States mails, return receipt requested, (a) to
Maker at 5427 Glenwick Lane, Dallas, Texas 75209 or (b) to Payee at Netpliance,
Inc., 7600A N. Capital of Texas Highway, Austin, Texas 78731. Either party may
change that party's above listed notice information by giving written notice of
the changed information to the other party at least ten days prior to such
change.

     10.  Governing law. This Note shall be construed and enforced in accordance
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with, and the rights of the parties shall be governed by, the law of the State
of Texas excluding (except for matters governed by the Uniform Commercial Code
as in effect in the State of Texas from time to time) choice of-law principles
of the law of such state that would require the application of the laws of a
jurisdiction other than such state.

     11.  Collection. If this Note is placed in the hands of an attorney for
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collection, or if it is collected through any legal proceedings at law or in
equity or in bankruptcy, receivership or other court proceedings, the Maker
promises to pay all costs and expenses of collection including, but not limited
to, court costs and the reasonable attorneys' fees of the holder hereof.

     12.  Non-recourse Obligation. Notwithstanding anything to the contrary
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contained in this Note or the Pledge Agreement, but without in any manner
affecting the validity of this Note or the Pledge Agreement, in the event of a
default or an event of default under this Note or under the terms of the Pledge
Agreement, or upon the maturity of this Note, whether by demand, acceleration,
the passage of time, or otherwise, the recourse of Payee shall be by the
exercise of the power of sale granted by the Pledge Agreement, or other remedies
set forth in the Pledge Agreement; and there shall be no personal liability of
Maker or of any of its trustees or beneficiaries for the payment of principal or
interest or other amounts that may become due and payable under the terms of
this Note, except for fraud or intentional misrepresentation made in or in
connection with this Note, the Pledge Agreement, or any other instrument
securing or in any way related to the indebtedness evidenced by this Note.
Except as otherwise provided in the immediately preceding sentence, Payee shall
look solely to the security of the property covered by the Pledge Agreement; and
no deficiency judgment for amounts unsatisfied after the application of such
security and the proceeds thereof shall ever be instituted, sought, taken, or
obtained against Maker or the trustees or beneficiaries of Maker for any amounts
that become due and owing.

                                               MAKER

                                               /s/ JAMES E. CAHILL
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                                               JAMES E. CAHILL


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