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                          REGISTRATION RIGHTS AGREEMENT

         This Agreement is made and entered into as of this ___th day of
________, 2000, by and among COMC, Inc., an Illinois corporation (the
"Company"), _______________, ___________ and ______________ being collectively
referred to herein as the "Investors").

1. CERTAIN DEFINITIONS.


         Section 1.1 As used in this Agreement, the following terms shall have
the following meanings:

               1.1 Commission means the Securities and Exchange Commission, or
any other federal agency at the time administering the Securities Act and the
Exchange Act.

               1.2 Common Stock means the Company's Common Stock, $.01 par
value.

               1.3 Exchange Act means the Securities Exchange Act of 1934, as
amended, or any similar federal statute, and the rules and regulations of the
Commission thereunder, all as the same shall be in effect at the time.

               1.4 Person means an individual, corporation, partnership, joint
venture, trust, or unincorporated organization, or a government or any agency or
political subdivision thereof.

               1.5 Registrable Securities means any shares of Common Stock owned
as of the date hereof or acquired hereafter by Investors or by their permitted
successors and assigns, including but not limited to shares of Common Stock
issued to Investors pursuant to the Stock Purchase Agreements, dated
____________, 2000, between the Company and each of the Investors and shares of
Common Stock acquired by the Investors pursuant to the exercise of options
granted by the Company in favor of the investors, but excluding any such shares
of Common Stock that have been (a) sold by such parties other than to a
permitted transferee of Investors, as defined in Section 5 hereof, (b)
registered under the Securities Act pursuant to an effective registration
statement filed thereunder and disposed of in accordance with the registration
statement covering such shares of Common Stock or (c) publicly sold pursuant to
Rule 144 of the Securities Act.

               1.6 Securities Act means the Securities Act of 1933, as amended,
or any similar federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

2. REGISTRATION RIGHTS.

         Section 2.1       Requested Registrations.

                   (a) Request for Registration. If at any time after the date
hereof, the Company shall receive from the Investors, holding at least 80% of
the Registrable Securities, a written request that the Company effect any
registration with respect to all or a part of the Registrable Securities, the
Company shall do the following:


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                   (i) within ten (10) days of receipt of such request from such
Investor(s), give written notice of the proposed registration to any other
Investors; and

                   (ii) as soon as practicable, but in any event no later than
ninety (90) days after receipt of such request from the Investor(s), file a
registration statement with the Commission, and use its best efforts to effect
such registration, including, without limitation, the execution of an
undertaking to file post-effective amendments, appropriate qualification under
applicable blue sky or other state securities laws (except that the Company
shall not be required to qualify the offering under the blue sky laws of any
jurisdiction in which the Company would be required to execute a general consent
to service of process unless the Company is already subject to service in such
jurisdiction), and appropriate compliance with applicable regulations issued
under the Securities Act, as may be so requested and as would permit or
facilitate the sale and distribution of all Registrable Securities as are
specified in such request, together with all Registrable Securities of any other
Investor joining in such request as are specified in a written request by the
other Investors within twenty (20) days after receipt of such written notice
from the Company.

                   (b) Underwriting.

                   (i) If the registration of which the Investors give notice is
for a registered public offering involving an underwriting, the Investors shall
so advise the Company as a part of their request made pursuant to Section 2.1
(a) above. The Company shall include such information in the written notice of
the Company referred to in Section 2.1(a)(i) above, including the name of the
underwriter or representative thereof selected for such underwriting. In such
event, the right of any Investor to registration pursuant to this Section 2.1
shall be conditioned upon such Investor participating in such underwriting and
the inclusion of such Investor's Registrable Securities in such underwriting to
the extent provided herein. Any underwriter requested by the Investors shall be
subject to the Company's approval.

                   (ii) The Company shall (together with all Investors proposing
to distribute their Registrable Securities through such underwriting) enter into
an underwriting agreement in customary form with the Underwriter or
representative thereof selected for such underwriting. Notwithstanding any other
provision of this Section 2.1, if the underwriter or representative thereof
advises the Investors in writing that, in its opinion, marketing factors require
a limitation on the number of shares to be underwritten, the number of shares of
Registrable Securities that are entitled to be included in the registration and
underwriting shall be allocated in the following manner: the securities of the
Company held by officers or directors (other than Registrable Securities) of the
Company and other stockholders, and the securities to be sold by the Company for
its own account shall be excluded from such registration to the extent so
required by such limitation, and if a limitation of the number of shares is
still required, the number of shares of Registrable Securities that may be
included in the registration and underwriting shall be allocated among all
Investors in proportion, as nearly as practicable, to the respective amounts of
Registrable Securities which they had requested to be included in such
registration at the time of filing, the registration statement. No Registrable


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Securities or any other securities excluded from the underwriting by reason of
the underwriter's marketing limitation shall be included in such registration.
If the Company or any holder of Registrable Securities, officer, director or
other stockholder who has requested inclusion in such registration as provided
above disapproves of the terms of any such underwriting, such person may elect
to withdraw therefrom by written notice to the Company, the underwriter and the
other Investors. The securities so withdrawn shall also be withdrawn from
registration. Any Registrable Securities or other securities excluded shall also
be withdrawn from such registration.

         Section 2.2 Piggyback Registrations. If at any time or times the
Company shall determine to register any of its Common Stock or securities
convertible into or exchangeable for Common Stock Under the Securities Act,
whether in connection with a public offering of securities by the Company (a
"primary offering"), a public offering thereof by stockholders (a "secondary
offering"), or both (but not in connection with a registration effected solely
to implement an employee benefit plan or a transaction to which Rule 145 or any
other similar rule of the Commission under the Securities Act is applicable),
the Company will promptly give written notice thereof to the Investors, and will
use its best efforts to effect the registration under the Securities Act of all
Registrable Securities in satisfaction of the Company's obligations under
Section 2.1; provided, however, that in the event that any registration pursuant
to this Section 2.1 shall be, in whole or in part, all underwritten public
offering of Common Stock, the number of shares of Registrable Securities to be
included in such an underwriting may be reduced (pro rata among Investors and
any other holder of Registrable Securities based upon the number of shares of
Registrable Securities owned by Investors and such holders) if and to the extent
that the managing underwriter shall be of the opinion that such inclusion would
adversely affect the marketing of the securities to be sold by the Company
therein; provided, however, that, prior to any such reduction, the Company shall
first exclude from such registration, in the following order, all shares of
Common Stock sought to be Included therein by (i) any holder thereof not having
any such contractual, incidental registration rights, and (ii) any holder
thereof having contractual, incidental registration rights subordinate or junior
to the rights of Investors. To the extent that the Company proposes to include
the Registrable Securities of any Investors in any primary or secondary offering
in accordance with this Section 2.2, and an Investor or Investors give notice
that they do not wish to be so included, the Company shall have no further
obligations hereunder with respect to such Investor or Investors.

         Section 2.3 Registration Expenses. In the event of a registration
described in Section 2.1, all reasonable expenses of registration and offering
of Investors including, without limitation, printing expenses, fees and
disbursements of counsel (limited to fees and expenses of a single attorney
jointly retained by Investors to represent Investors as a group), and
independent public accountants, shall be borne by the Company, except that each
of the Investors shall bear underwriting commissions and discounts attributable
to his Registrable Securities being registered.

         Section 2.4 Further Obligations of the Company. Whenever, under the
preceding sections of this Agreement, the Company is required hereunder to
register


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Registrable Securities, it agrees that it shall also do the following:

               (a) Use its best efforts to diligently prepare for filing with
the Commission a registration statement and such amendments and supplements to
said registration statement and the prospectus used in connection therewith as
may be necessary to keep said registration statement effective for a period of
at least 270 days and to comply with the provisions of the Securities Act with
respect to the sale of securities covered by said registration statement for the
period necessary to complete the proposed public offering;

               (b) Furnish to Investors such copies of each preliminary and
final prospectus and such other documents as such holder may reasonably request
to facilitate the public offering of his Registrable Securities;

               (c) Enter into any underwriting agreement with provisions
reasonably required by the proposed underwriter for Investor, if any, and
reasonably acceptable to the Company; and

               (d) Use best efforts to register or qualify the Registrable
Securities covered by said registration statement under the securities or
"blue-sky" laws of such jurisdictions as Investor may reasonably request.

3. INDEMNIFICATION. Incident to any registration referred to in this agreement,
and subject to applicable law, the Company will indemnify each underwriter, each
Investor, and each person controlling any of them against all claims, losses,
damages and liabilities, including legal and other expenses reasonably incurred
in investigating or defending against the same, arising out of any untrue
statement of a material fact contained in any prospectus or other document
(including any related registration statement) or any omission to state therein
a material fact required to be stated therein or necessary to make the
statements therein not misleading, or arising out of any violation by the
Company of the Securities Act, any state securities or "blue-sky" laws or any
rule or regulation thereunder in connection with such registration; provided,
however, that the Company will not be liable in any case to the extent that any
such claim, loss, damage or liability (i) may have been caused by an untrue
statement or omission which is based upon information furnished in writing to
the Company by Investors expressly for use therein, or (ii) may have been
suffered or incurred by the Company and resulted from an action, claim or suit
by a Person who purchased Registrable Securities or other securities of the
Company from any of the Investors in reliance upon any untrue statement or
omission which was contained or made in any preliminary prospectus furnished by
Investor to such Person in connection with such registration and which was
corrected in a final prospectus which such Investor possessed, but which such
Investor failed to deliver or provide a copy of such final prospectus to such
Person at or prior to the confirmation of the sale of any such Registrable
Securities in any case where such delivery is required by the Securities Act. In
the event of any registration of any of the Registrable Securities under the
Securities Act pursuant to this Agreement, each Investor will indemnify and hold
harmless the Company, each of its directors and officers and each underwriter
(if any) and each if any, who controls the Company or any such underwriter
within the


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meaning of the Securities Act or the Exchange Act against any claim,
losses, damages and liabilities, including legal and other expenses reasonably
incurred in investigating or defending it against the same, (i) arising out of
any untrue statement of a material fact contained in any prospectus or other
document (including any related registration statement) or any omission to state
therein a material fact required to be stated therein or necessary to make the
statement therein not misleading, if the statement or omission was made in
reliance upon and in conformity with information furnished in writing to the
Company by or on behalf of such Investor, specifically for use in connection
with the preparation of such registration statement, prospectus, amendment or
supplement, or (ii) which may have been suffered or incurred by the Company and
which resulted from an action, claim or suit by a Person who purchased
Registrable Securities or other securities of the Company from Investor in
reliance upon any untrue statement or omission which was contained or made in
any preliminary prospectus furnished by such investor to such Person and which
was corrected in a final prospectus which Investor possessed, but which such
Investor failed to deliver or provide a copy of such final prospectus to such
Person at or prior to the confirmation of the sale of any such Registrable
Securities in any case where such delivery is required by the Securities Act.

4. RULE 144 REQUIREMENTS. If the Company remains subject to the reporting
requirements of either Section 13 or Section 15(d) of the Exchange Act, the
Company will use its best efforts to file with the Commission such information
as the Commission may require under either of said sections; and in such event,
the Company shall use its best efforts to take all action as may be required as
a condition to the availability of Rule 144 of the Securities Act (or any
Successor exemptive rule hereinafter ill effect). The Company shall furnish to
such Investor upon request, a written statement executed by the Company as to
the steps it has taken to comply with the current public information
requirements of Rule 144.

5. TRANSFER OF REGISTRATION RIGHTS. The registration rights of Investors under
this Agreement may be transferred to any transferee of any Registrable
Securities, who (i) is a holder of Registrable Securities as of the date of this
Agreement, (ii) is an affiliate of an entity that holds Registrable Securities,
as "affiliate" is defined in the Investment Company Act of 1940, as of the date
of this Agreement (including a partner of such holder), or (iii) acquires at
least 10,000 shares of Registrable Securities (as adjusted for stock splits,
stock dividends, reclassification, recapitalizations or other similar events).
Each such transferee shall be deemed to be an "Investor" for purposes of this
Agreement; provided, however, that no transfer of registration rights by
Investor pursuant to this Section 5 shall create any additional rights in the
transferee beyond those rights granted to Investors Pursuant to this Agreement.

6. MISCELLANEOUS.

         Section 6.1 Damages. The Company recognizes and agrees that Investors
will not have all adequate remedy if the Company falls to comply with this
Agreement and that damages may not be readily ascertainable, and the Company
expressly agrees that, in the event of such failure, it shall not oppose all
application by any Investor requiring specific performance of any and all
provisions hereof or enjoining the Company from continuing to commit any such
breach of this Agreement.


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         Section 6.2 No Waiver, Cumulative Remedies. No failure or delay on the
part of any party to this Agreement in exercising any right, power or remedy
hereunder shall operate as a waiver thereof, nor shall any single or partial
exercise of any such right, power or remedy preclude any other or further
exercise thereof or the exercise of any other right, power or remedy hereunder.
The remedies herein provided are cumulative and not exclusive of any remedies
provided by law.

         Section 6.3 Amendments and Waivers. Except as hereinafter provided,
amendments to this Agreement shall require and shall be effective upon receipt
of the written consent of both the Company and Investors. Except as hereinafter
provided, compliance with any covenant or provision set forth herein may be
waived upon written consent by the party or parties whose rights are being
waived. Any waiver or amendments may be given subject to satisfaction of
conditions stated therein and any waiver or amendments shall be effective only
in the specific instance and for the specific purpose for which given.

         Section 6.4       Notices.

         As the terms "notice" or "notices" are used herein as between the
parties, such term shall mean a written document, explaining the reason for the
notice, and the same shall be mailed by United States Postal Service Via
Certified Mail, Return Receipt Requested, addressed as follows:

        If to the Company:   COMC, Inc.
                             2840 Howe Road, Suite D
                             Martinez, CA 94553-4000
                             Attention: Chief Financial Officer
                             Fax No.: (925) 335-4007

         with a copy to:     Scott Smith, Esq.
                             McCutchen Doyle Brown Enersen LLP
                             Three Embarcadero Center
                             San Francisco, California  94111
                             Fax No. (415) 393-2106


         If to Investors: to the respective address set forth on Schedule I
attached hereto.

Such notice shall be deemed to have been given on the date placed in the U.S.
Mails, and sent by fax to counsel, whether actually received by the addressee or
not. The parties shall, as a matter of convenience and courtesy, send each party
receiving notice a copy of said notice by facsimile or other electronic means,
or by courier, Federal Express, or similar service, but such notifications shall
not be deemed lawful "notice" as required hereby. The parties may, from time to
time, amend the above addresses and names by written notice to the other party.

         Section 6.5 Binding Effect; Assignment. This Agreement shall be binding
upon and inure to the benefit of the parties hereto and their respective heirs,
successors and assigns, except that the Company shall not have the right to
delegate its obligations hereunder or to assign its rights hereunder or any
interest herein without the prior written consent of all of the Investors.


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         Section 6.6 Prior Agreements. This Agreement constitutes the entire
agreement between the parties and Supersedes any prior understandings or
agreements concerning the subject matter hereof.

         Section 6.7 Severability. The provisions of this Agreement are
severable and, in the event that any court of competent Jurisdiction shall
determine that any one or more of the provisions or part of a provision
contained in this Agreement, shall, for any reason, be held to be invalid,
illegal or unenforceable such invalidity, illegality or unenforceability shall
not affect any other provision or part of a provision of this Agreement, but
instead this Agreement shall be reformed and construed as if such invalid or
illegal or unenforceable provision, or part of a provision, had never been
contained herein, and such provisions or part reformed so that it would be
valid, legal and enforceable to the maximum extent possible.

         Section 6.8 Governing Law. This Agreement shall be governed by and
construed in accordance with the substantive laws of the State of California.

         Section 6.9 Headings. Article, section and subsection headings in this
Agreement are included herein for convenience of reference only and shall not
constitute a part of this Agreement for any other purpose.

         Section 6.10 Counterparts. This Agreement maybe executed in any number
of counterparts, all of which taken together shall constitute one and the same
instrument, and any of the parties hereto may execute this Agreement by signing
any such counterpart.

         Section 6.11 Further Assurances. From and after the date of this
Agreement, upon the request of any party hereto, the other parties shall execute
and deliver such instruments, documents and other writings as may be reasonably
necessary or desirable to confirm and carry out and to effectuate fully the
intent and purposes of this Agreement.


         [the remainder of this page has been intentionally left blank]



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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed on the day and year first above written.


COMC, Inc.


By: --------------------------------
Name:    John J. Ackerman
Title:   Chairman


INVESTORS:


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