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                                                                   Exhibit 10.16


                             STOCK OPTION AGREEMENT


        Boulder Capital Opportunities, Inc., a Colorado corporation ("Company"),
desiring to afford an opportunity to the Grantee named below to purchase certain
shares of the Company's Common Stock, no par value, to provide the Grantee with
an added incentive as an employee of the Company or of one or more of its
subsidiaries, hereby grants to Grantee, and the Grantee accepts, an option (the
"Option") to purchase the number of such shares optioned as specified below,
during the term ending at midnight (prevailing local time at the Company's
principal offices) on the expiration date of this Option specified below, at the
option exercise price specified below, subject to and upon the following terms
and conditions:

        1. Identifying Provisions: As used in this Option, the following terms
shall have the following meanings:

<TABLE>
<S>                                                      <C>
               (a)    Grantee:                            Dave Medinnis

               (b)    Date of Grant:                      July 23, 1999

               (c)    Number of Shares optioned:          Fifty Thousand (50,000)

               (d)    Option exercise price per share:    Two and 50/100 Dollars ($2.50)

               (e)    Expiration Date:                    July 22, 2004
</TABLE>

        2. Timing of Purchases: Subject to the provisions for termination and
acceleration, this Option shall become exercisable in installments as follows:

           (a) after April 1, 2000, up to fifty percent (50%) of the total
number of shares optioned; and

           (b) after April 1, 2001, up to all of the optioned shares until and
including the expiration date of the Option whereupon the Option shall expire
and may thereafter no longer be exercised.

        The Company hereby agrees that at all times there shall be reserved for
issuance and delivery upon exercise of the Option such number of shares of its
Common Stock as shall be required for issuance and delivery upon full exercise
of the Option.

        3. Restrictions on Exercise: The following additional provisions shall
apply to the exercise of the Option:

           (a) Termination of Employment. If the Grantee's employment by the
Company or any of its subsidiaries is terminated for any reason other than death
only that portion of this Option exercisable at the time of such termination of
employment may thereafter be exercised, and it may not be exercised more than
three (3) months after such termination nor after the expiration date of this
Option, whichever date is sooner, unless such termination is by reason of the
Grantee's permanent and total disability, in which case such period of three (3)
months shall be extended to one (1) year. In all other respects, this Option
shall terminate upon such termination of employment.


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Boulder Capital Opportunities, Inc.
Stock Option Agreement
As of July 23, 1999
Page 2



           (b) Death of Grantee. If the Grantee shall die during the term of
this Option, the Grantee's legal representative or representatives, or the
person or persons entitled to do so under the Grantee's last will and testament
or under applicable intestate laws, shall have the right to exercise this
Option, but only for the number of shares as to which the Grantee was entitled
to exercise this Option in accordance with Section 2 hereof on the date of his
death, and such right shall expire and this Option shall terminate one (1) year
after the date of the Grantee's death or on the expiration date of this Option,
whichever date is sooner. In all other respects, this Option shall terminate
upon such death.

           (c) Continuity of Employment. This Option shall not be exercisable by
the Grantee in any part unless at all times beginning with the date of grant and
ending no more than three (3) months prior to the date of exercise, the Grantee
has, except for military service leave, sick leave or other bona fide leave of
absence (such as temporary employment by the United States Government) been in
the continuous employ of the Company or a parent or subsidiary thereof, except
that such period of three (3) months shall be one (1) year following any
termination of the Grantee's employment by reason of his permanent and total
disability.

        4. Non-Transferable: The Grantee may not transfer this Option except by
will or the laws of descent and distribution. This Option shall not be otherwise
transferred, assigned, pledged, hypothecated or disposed of in any way, whether
by operation of law or otherwise, and shall be exercisable during the Grantee's
lifetime only by the Grantee or his guardian or legal representative.

        5. Rights in Shares Before Issuance and Delivery: No person, including
the Grantee, shall be entitled to the privileges of stock ownership in respect
of any shares issuable upon exercise of this Option, unless and until such
shares have been issued to such person as fully paid shares.

        6. Adjustments and Corporate Reorganizations: If the Company shall at
any time issue Common Stock by way of dividend or other distribution on any
stock of the Company or subdivide or combine the outstanding shares of Common
Stock, then the exercise price shall be proportionately decreased in the case of
such issuance (on the day following the date fixed for determining shareholders
entitled to receive such dividend or other distribution), or decreased in the
case of such subdivision, or increased in the case of such combination (on the
date that such subdivision or combination shall become effective). Upon any
adjustment of the exercise price, Grantee shall thereafter (until another such
adjustment) be entitled to purchase, at the new exercise price, the number of
shares, calculated to the nearest full share, obtained by multiplying the number
of shares of Common Stock initially issuable upon exercise of the Option by the
exercise price in effect on the date hereof and dividing the product so obtained
by the new exercise price.

        In the event of any reclassification, capital reorganization or other
change of outstanding shares of Common Stock (other than as a result of an
issuance of Common Stock by way of dividend or other distribution or of a
subdivision or combination), or in case of any consolidation or merger of the
Company with or into another corporation (other than a merger with a subsidiary
in which merger the Company is the continuing corporation and which does not
result in any reclassification, capital reorganization or other change of
outstanding shares of Common Stock of the class issuable upon exercise of the
Option), or in case of any sale or conveyance to any other corporation of the
property and assets of the Company as an entirety or substantially as an
entirety, as a condition to any of the foregoing, the Company shall cause
effective provision to be made (including acceleration of vesting) so that
Grantee


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Boulder Capital Opportunities, Inc.
Stock Option Agreement
As of July 23, 1999
Page 3



shall have the right thereafter, by exercising the Option, to purchase the kind
and amount of shares of stock and other securities and property receivable upon
such reclassification, capital reorganization or other change, consolidation,
merger, sale or conveyance as if Grantee had exercised the Option prior to such
transaction. Any such provision shall include provision for adjustments which
shall be as nearly equivalent as may be practicable to the adjustments provided
for in the Option. The foregoing provisions shall similarly apply to successive
reclassifications, capital reorganizations and changes of shares of Common Stock
and to successive consolidations, mergers, sales or conveyances.

        In the event the Company spins off a subsidiary by distributing to the
shareholders of the Company, as a dividend or otherwise, the stock of the
subsidiary, the Company shall reserve, for the life of the Option, shares of the
subsidiary to be delivered to Grantee upon exercising the Option to the same
extent as if Grantee were the owner of record of Common Stock on the record date
for payment of the shares of the subsidiary.

        7. Exercise, Payment for and Delivery of Stock: Each exercise of the
Option shall be accomplished by presentation and delivery to the Company of a
notice of exercise, duly executed and accompanied by payment of the exercise
price for the number of shares of Common Stock specified in such notice of
exercise, together with all Federal and state taxes applicable upon such
exercise.

        8. Restricted Stock Provisions: Shares of stock issued on exercise of
this Option shall upon issuance be restricted securities as such term is defined
in Rule 144(a)(3) of the Securities Act of 1933, as amended. In addition, if the
employment of the Grantee with the Company or a subsidiary of the Company is
terminated for any reason other than Cause, then the Option vesting period shall
be accelerated to coincide with said act of termination; provided, however, that
such acceleration of vesting shall not occur if Grantee leaves voluntarily. The
restrictions imposed under this paragraph shall apply as well to all shares or
other securities issued in respect of restricted stock in connection with any
stock split, reverse stock split, stock dividend, recapitalization,
reclassification, spin-off, split-off, merger, consolidation or reorganization.
For purposes of this paragraph, the term "Cause" shall mean the occurrence of
any of the following events: (i) if Grantee shall be found guilty of fraud,
dishonesty, misappropriation of funds, embezzlement, or other acts of misconduct
in the rendering of services on behalf of Company; (ii) for Grantee's scandalous
or grossly immoral, felonious, improper or unethical conduct; or (iii) if
Grantee willfully and continuously fails or refuses to comply with the policies,
standards and regulations of Company as are from time to time established in the
reasonable discretion of the Company's Board of Directors.

        9. Notices: Any notice to be given to the Company shall be addressed to
the Company in care of its Secretary at its principal office, and any notice to
be given to the Grantee shall be addressed to him at the address beneath his
signature hereto or at such other address as the Grantee may hereafter designate
in writing to the Company. Any such notice shall be deemed duly given when
addressed as aforesaid, registered or certified, and deposited, postage and
registry or certification fee prepaid, in a post office or branch post office
regularly maintained by the United States Postal Service.

        10. Governing Law: This Agreement shall be governed by the laws of the
State of California without regard to principles of conflicts of laws.



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Boulder Capital Opportunities, Inc.
Stock Option Agreement
As of July 23, 1999
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        IN WITNESS WHEREOF, the Company has granted this Option on the date of
grant specified above.

                                       BOULDER CAPITAL OPPORTUNITIES, INC.


                                       By: /s/ Gill Champion
                                           -----------------------------------
                                           Its: Chief Operating Officer
                                                -------------------------------

AGREED AND ACCEPTED AS OF
THIS 23RD DAY OF JULY, 1999.


 /s/ Dave Medinnis
-----------------------------------
Dave Medinnis


 2536 Parkland Ct.
-----------------------------------
Street Address


 Santa Clara, CA
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City and State