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                                                                   EXHIBIT 10.33


                                 METRICOM, INC.

                     1997 NON-OFFICER EQUITY INCENTIVE PLAN

                ADOPTED BY THE BOARD OF DIRECTORS ON MAY 1, 1997


1. PURPOSES.

         (a) The purpose of the Plan is to provide a means by which selected
Employees of and Consultants to the Company, and its Affiliates, may be given an
opportunity to benefit from increases in value of the Company's common stock
("Common Stock") through the granting of (i) Nonstatutory Stock Options, (ii)
stock bonuses, and (iii) rights to purchase restricted stock, all as defined
below.

         (b) The Company, by means of the Plan, seeks to retain the services of
persons (other than persons serving as Officers or Directors of the Company or
its Affiliates) who are now Employees of or Consultants to the Company or its
Affiliates, to secure and retain the services of new Employees and Consultants,
and to provide incentives for such persons to exert maximum efforts for the
success of the Company and its Affiliates.

         (c) The Company intends that the Stock Awards issued under the Plan
shall, in the discretion of the Board or any Committee to which responsibility
for administration of the Plan has been delegated pursuant to subsection 3(c),
be either (i) Nonstatutory Stock Options granted pursuant to Section 6 hereof,
or (ii) stock bonuses or rights to purchase restricted stock granted pursuant to
Section 7 hereof.

2. DEFINITIONS.

         (a) "AFFILIATE" means any parent corporation or subsidiary corporation,
whether now or hereafter existing, as those terms are defined in Sections 424(e)
and (f), respectively, of the Code.

         (b) "BOARD" means the Board of Directors of the Company.

         (c) "CODE" means the Internal Revenue Code of 1986, as amended.

         (d) "COMMITTEE" means a Committee appointed by the Board in accordance
with subsection 3(c) of the Plan.

         (e) "COMPANY" means Metricom, Inc., a Delaware corporation.

         (f) "CONSULTANT" means any person, including an advisor, engaged by the
Company or an Affiliate to render consulting services and who is compensated for
such services, provided that the term "Consultant" shall not include those
persons who render services as a Director.

                                       1.
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         (g) "CONTINUOUS STATUS AS AN EMPLOYEE OR CONSULTANT" means that the
service of an individual to the Company, whether as an Employee or Consultant,
is not interrupted or terminated. The Board, in its sole discretion, may
determine whether Continuous Status as an Employee or Consultant shall be
considered interrupted in the case of: (i) any leave of absence approved by the
Board, including sick leave, military leave, or any other personal leave; or
(ii) transfers between locations of the Company or between the Company,
Affiliates or their successors.

         (h) "DIRECTOR" means a member of the Board.

         (i) "DISABILITY" means permanent and total disability as defined in
Section 22(e)(3) of the Code.

         (j) "EMPLOYEE" means any person employed by the Company or any
Affiliate of the Company. Neither service as a Director nor payment of a
director's fee by the Company shall be sufficient to constitute "employment" by
the Company.

         (k) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended.

         (l) "FAIR MARKET VALUE" means, as of any date, the value of the Common
Stock, determined as follows:

                  (1) If the Common Stock is listed on any established stock
exchange or traded on the Nasdaq National Market or The Nasdaq SmallCap Market,
the Fair Market Value of a share of Common Stock shall be the closing sales
price for such stock (or the closing bid, if no sales were reported) as quoted
on such exchange or market (or the exchange or market with the greatest volume
of trading in the Common Stock) on the last market trading day prior to the day
of determination, as reported in The Wall Street Journal or such other source as
the Board deems reliable.

                  (2) In the absence of such markets for the Common Stock, the
Fair Market Value shall be determined in good faith by the Board.

         (m) "NONSTATUTORY STOCK OPTION" means an Option not intended to qualify
as an incentive stock option pursuant to Section 422 of the Code and the
regulations promulgated thereunder.

         (n) "OFFICER" means a person who is an officer of the Company within
the meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.

         (o) "OPTION" means a stock option granted pursuant to the Plan.

         (p) "OPTION AGREEMENT" means a written agreement between the Company
and an Optionee evidencing the terms and conditions of an individual Option
grant. Each Option Agreement shall be subject to the terms and conditions of the
Plan.


                                       2.
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         (q) "OPTIONEE" means an Employee or Consultant who holds an outstanding
Option.

         (r) "PLAN" means this 1997 Non-Officer Equity Incentive Plan.

         (s) "STOCK AWARD" means any right granted under the Plan, including any
Option, any stock bonus and any right to purchase restricted stock.

         (t) "STOCK AWARD AGREEMENT" means a written agreement between the
Company and a holder of a Stock Award evidencing the terms and conditions of an
individual Stock Award grant. Each Stock Award Agreement shall be subject to the
terms and conditions of the Plan.

3. ADMINISTRATION.

         (a) The Plan shall be administered by the Board unless and until the
Board delegates administration to a Committee, as provided in subsection 3(c).

         (b) The Board shall have the power, subject to, and within the
limitations of, the express provisions of the Plan:

                  (1) To determine from time to time which of the persons
eligible under the Plan shall be granted Stock Awards; when and how each Stock
Award shall be granted; whether a Stock Award will be a Nonstatutory Stock
Option, a stock bonus, a right to purchase restricted stock, or a combination of
the foregoing; the provisions of each Stock Award granted (which need not be
identical), including the time or times when a person shall be permitted to
receive stock pursuant to a Stock Award; and the number of shares with respect
to which a Stock Award shall be granted to each such person.

                  (2) To construe and interpret the Plan and Stock Awards
granted under it, and to establish, amend and revoke rules and regulations for
its administration. The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan or in any Stock Award Agreement,
in a manner and to the extent it shall deem necessary or expedient to make the
Plan fully effective.

                  (3) To amend the Plan or a Stock Award as provided in Section
12.

                  (4) Generally, to exercise such powers and to perform such
acts as the Board deems necessary or expedient to promote the best interests of
the Company which are not in conflict with the provisions of the Plan.

         (c) The Board may delegate administration of the Plan to a committee
composed of one or more members of the Board (the "Committee"). If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the Board (and references in this Plan to the Board shall thereafter be to
the Committee), subject, however, to such resolutions, not inconsistent with the
provisions of the Plan, as may be adopted from time to time by the Board. The
Board may abolish the Committee at any time and revest in the Board the
administration of the Plan.

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4. SHARES SUBJECT TO THE PLAN.

         (a) Subject to the provisions of Section 11 relating to adjustments
upon changes in stock, the number of shares of stock that may be issued pursuant
to Stock Awards shall not exceed in the aggregate six hundred seventy-five
thousand (675,000) shares of Common Stock. If any Stock Award shall for any
reason expire or otherwise terminate, in whole or in part, without having been
exercised in full, the stock not acquired under such Stock Award shall revert to
and again become available for issuance under the Plan.

         (b) The stock subject to the Plan may be unissued shares or reacquired
shares, bought on the market or otherwise.

5. ELIGIBILITY.

         Stock Awards may be granted only to Employees or Consultants who are
not (i) Officers, (ii) Directors, or (iii) then subject to Section 16 of the
Exchange Act.

6. OPTION PROVISIONS.

         Each Option shall be in such form and shall contain such terms and
conditions as the Board shall deem appropriate. The provisions of separate
Options need not be identical, but each Option shall include (through
incorporation of provisions hereof by reference in the Option or otherwise) the
substance of each of the following provisions:

         (a) TERM. No Option shall be exercisable after the expiration of ten
(10) years from the date it was granted.

         (b) PRICE. The exercise price of each Nonstatutory Stock Option shall
be not less than eighty-five percent (85%) of the Fair Market Value of the stock
subject to the Option on the date the Option is granted.

         (c) CONSIDERATION. The purchase price of stock acquired pursuant to an
Option shall be paid, to the extent permitted by applicable statutes and
regulations, either (i) in cash at the time the Option is exercised, or (ii) at
the discretion of the Board or the Committee, at the time of the grant of the
Option, (A) by delivery to the Company of other shares of Common Stock, (B)
according to a deferred payment arrangement, except that payment of the Common
Stock's "par value" (as defined in the Delaware General Corporation Law) shall
not be made by deferred payment or other arrangement (which may include, without
limiting the generality of the foregoing, the use of other shares of Common
Stock) with the person to whom the Option is granted or to whom the Option is
transferred pursuant to subsection 6(d), or (C) in any other form of legal
consideration that may be acceptable to the Board. In the case of any deferred
payment arrangement, interest shall be payable at least annually and shall be
charged at the minimum rate of interest necessary to avoid the treatment as
interest, under any applicable provisions of the Code, of any amounts other than
amounts stated to be interest under the deferred payment arrangement.


                                       4.
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         (d) TRANSFERABILITY. An Option may be transferred to the extent
provided in the Option Agreement; provided that if the Option Agreement does not
expressly permit the transfer of an Option, the Option shall not be transferable
except by will, by the laws of descent and distribution or pursuant to a
domestic relations order satisfying the requirements of Rule 16b-3, and shall be
exercisable during the lifetime of the person to whom the Option is granted only
by such person or any transferee pursuant to a domestic relations order.
Notwithstanding the foregoing, the person to whom the Option is granted may, by
delivering written notice to the Company, in a form satisfactory to the Company,
designate a third party who, in the event of the death of the Optionee, shall
thereafter be entitled to exercise the Option.

         (e) VESTING. The total number of shares of stock subject to an Option
may, but need not, be allotted in periodic installments (which may, but need
not, be equal). The Option Agreement may provide that from time to time during
each of such installment periods, the Option may become exercisable ("vest")
with respect to some or all of the shares allotted to that period, and may be
exercised with respect to some or all of the shares allotted to such period
and/or any prior period as to which the Option became vested but was not fully
exercised. The Option may be subject to such other terms and conditions on the
time or times when it may be exercised (which may be based on performance or
other criteria) as the Board may deem appropriate. The vesting provisions of
individual Options may vary. The provisions of this subsection 6(e) are subject
to any Option provisions governing the minimum number of shares as to which an
Option may be exercised.

         (f) TERMINATION OF EMPLOYMENT OR CONSULTING RELATIONSHIP. In the event
an Optionee's Continuous Status as an Employee or Consultant terminates (other
than upon the Optionee's death or disability), the Optionee may exercise his or
her Option within such period of time designated by the Board, which shall in no
event be later than the expiration of the term of the Option as set forth in the
Option Agreement (the "Post-Termination Exercise Period") and only to the extent
that the Optionee was entitled to exercise the Option on the date Optionee's
Continuous Status as an Employee or Consultant terminates. The Board may at any
time, with the consent of the Optionee, extend the Post-Termination Exercise
Period and provide for continued vesting. If, at the date of termination, the
Optionee is not entitled to exercise his or her entire Option, the shares
covered by the unexercisable portion of the Option shall revert to the Plan. If,
after termination, the Optionee does not exercise his or her Option within the
time specified in the Option Agreement or as otherwise determined above, the
Option shall terminate, and the shares covered by such Option shall revert to
the Plan. Notwithstanding the foregoing, the Board shall have the power to
permit an Option to continue to vest during the Post-Termination Exercise
Period.

         An Optionee's Option Agreement may also provide that if the exercise of
the Option following the termination of the Optionee's Continuous Status as an
Employee or Consultant (other than upon the Optionee's death or disability)
would result in liability under Section 16(b) of the Exchange Act, then the
Option shall terminate on the earlier of (i) the expiration of the term of the
Option set forth in the Option Agreement, or (ii) the tenth (10th) day after the
last date on which such exercise would result in such liability under Section
16(b) of the Exchange Act. Finally, an Optionee's Option Agreement may also
provide that if the exercise of the Option following the termination of the
Optionee's Continuous Status as an Employee or

                                       5.
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Consultant (other than upon the Optionee's death or disability) would be
prohibited at any time solely because the issuance of shares would violate the
registration requirements under the Act, then the Option shall terminate on the
earlier of (i) the expiration of the term of the Option set forth in the first
paragraph of this subsection 6(f), or (ii) the expiration of a period of three
(3) months after the termination of the Optionee's Continuous Status as an
Employee or Consultant during which the exercise of the Option would not be in
violation of such registration requirements.

         (g) DISABILITY OF OPTIONEE. In the event an Optionee's Continuous
Status as an Employee or Consultant terminates as a result of the Optionee's
Disability, the Optionee may exercise his or her Option (to the extent that the
Optionee was entitled to exercise it as of the date of termination), but only
within such period of time ending on the earlier of (i) the date twelve (12)
months following such termination (or such longer or shorter period specified in
the Option Agreement), or (ii) the expiration of the term of the Option as set
forth in the Option Agreement. If, at the date of termination, the Optionee is
not entitled to exercise his or her entire Option, the shares covered by the
unexercisable portion of the Option shall revert to and again become available
for issuance under the Plan. If, after termination, the Optionee does not
exercise his or her Option within the time specified herein, the Option shall
terminate, and the shares covered by such Option shall revert to and again
become available for issuance under the Plan.

         (h) DEATH OF OPTIONEE. In the event of the death of an Optionee during,
or within a period specified in the Option Agreement after the termination of,
the Optionee's Continuous Status as an Employee or Consultant, the Option may be
exercised (to the extent the Optionee was entitled to exercise the Option as of
the date of death) by the Optionee's estate, by a person who acquired the right
to exercise the Option by bequest or inheritance, but only within the period
ending on the earlier of (i) the date eighteen (18) months following the date of
death (or such longer or shorter period specified in the Option Agreement), or
(ii) the expiration of the term of such Option as set forth in the Option
Agreement. If, at the time of death, the Optionee was not entitled to exercise
his or her entire Option, the shares covered by the unexercisable portion of the
Option shall revert to and again become available for issuance under the Plan.
If, after death, the Option is not exercised within the time specified herein,
the Option shall terminate, and the shares covered by such Option shall revert
to and again become available for issuance under the Plan.

7. TERMS OF STOCK BONUSES AND PURCHASES OF RESTRICTED STOCK.

         Each stock bonus or restricted stock purchase agreement shall be in
such form and shall contain such terms and conditions as the Board or the
Committee shall deem appropriate. The terms and conditions of stock bonus or
restricted stock purchase agreements may change from time to time, and the terms
and conditions of separate agreements need not be identical, but each stock
bonus or restricted stock purchase agreement shall include (through
incorporation of provisions hereof by reference in the agreement or otherwise)
the substance of each of the following provisions as appropriate:


                                       6.
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         (a) PURCHASE PRICE. The purchase price under each restricted stock
purchase agreement shall be such amount as the Board or Committee shall
determine and designate in such agreement, but in no event shall the purchase
price be less than eighty-five percent (85%) of the Fair Market Value of the
Common Stock on the date such award is made. Notwithstanding the foregoing, the
Board or the Committee may determine that eligible participants in the Plan may
be awarded stock pursuant to a stock bonus agreement in consideration for past
services actually rendered to the Company or for its benefit.

         (b) TRANSFERABILITY. No rights under a stock bonus or restricted stock
purchase agreement shall be transferable except by will or the laws of descent
and distribution, unless the applicable Stock Award Agreement expressly provides
for other transferability.

         (c) CONSIDERATION. The purchase price of stock acquired pursuant to a
stock purchase agreement shall be paid either: (i) in cash at the time of
purchase; (ii) at the discretion of the Board or the Committee, according to a
deferred payment or other arrangement, except that payment of the Common Stock's
"par value" (as defined in the Delaware General Corporation Law) shall not be
made by deferred payment or other arrangement (which may include, without
limiting the generality of the foregoing, the use of other shares of Common
Stock) with the person to whom the stock is sold; or (iii) in any other form of
legal consideration that may be acceptable to the Board or the Committee in its
discretion. Notwithstanding the foregoing, the Board or the Committee to which
administration of the Plan has been delegated may award stock pursuant to a
stock bonus agreement in consideration for past services actually rendered to
the Company or for its benefit.

         (d) VESTING. Shares of stock sold or awarded under the Plan may, but
need not, be subject to a repurchase option in favor of the Company in
accordance with a vesting schedule to be determined by the Board or the
Committee.

         (e) TERMINATION OF EMPLOYMENT OR CONSULTING RELATIONSHIP. In the event
a Participant's Continuous Status as an Employee or Consultant terminates, the
Company may repurchase or otherwise reacquire, subject to the limitations
described in subsection 7(d), any or all of the shares of stock held by that
person which have not vested as of the date of termination under the terms of
the stock bonus or restricted stock purchase agreement between the Company and
such person.

8. COVENANTS OF THE COMPANY.

         (a) During the terms of the Stock Awards, the Company shall keep
available at all times the number of shares of stock required to satisfy such
Stock Awards.

         (b) The Company shall seek to obtain from each regulatory commission or
agency having jurisdiction over the Plan such authority as may be required to
issue and sell shares of stock upon exercise of the Stock Award; provided,
however, that this undertaking shall not require the Company to register under
the Securities Act of 1933, as amended (the "Securities Act") either the Plan,
any Stock Award or any stock issued or issuable pursuant to any such Stock
Award. If, after reasonable efforts, the Company is unable to obtain from any
such

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regulatory commission or agency the authority which counsel for the Company
deems necessary for the lawful issuance and sale of stock under the Plan, the
Company shall be relieved from any liability for failure to issue and sell stock
upon exercise of such Stock Awards unless and until such authority is obtained.

9.  USE OF PROCEEDS FROM STOCK.

         Proceeds from the sale of stock pursuant to Stock Awards shall
constitute general funds of the Company.

10. MISCELLANEOUS.

         (a) The Board shall have the power to accelerate the time at which a
Stock Award may first be exercised or the time during which a Stock Award or any
part thereof will vest pursuant to subsection 6(e) or 7(d), notwithstanding the
provisions in the Stock Award stating the time at which it may first be
exercised or the time during which it will vest.

         (b) Neither an Employee or Consultant, nor any person to whom a Stock
Award is transferred under subsection 6(d) or 7(b) shall be deemed to be the
holder of, or to have any of the rights of a holder with respect to, any shares
subject to such Stock Award unless and until such person has satisfied all
requirements for exercise of the Stock Award pursuant to its terms.

         (c) Nothing in the Plan or any instrument executed or Stock Award
granted pursuant thereto shall confer upon any Employee, Consultant or other
holder of Stock Awards any right to continue in the employ of the Company or any
Affiliate (or to continue acting as a Consultant) or shall affect the right of
the Company or any Affiliate to terminate the employment of any Employee with or
without cause, or to terminate the relationship of any Consultant in accordance
with the terms of that Consultant's agreement with the Company or Affiliate to
which such Consultant is providing services.

         (d) The Company may require any person to whom a Stock Award is
granted, or any person to whom a Stock Award is transferred pursuant to
subsection 6(d) or 7(b), as a condition of exercising or acquiring stock under
any Stock Award, (1) to give written assurances satisfactory to the Company as
to such person's knowledge and experience in financial and business matters
and/or to employ a purchaser representative reasonably satisfactory to the
Company who is knowledgeable and experienced in financial and business matters,
and that he or she is capable of evaluating, alone or together with the
purchaser representative, the merits and risks of exercising the Stock Award;
and (2) to give written assurances satisfactory to the Company stating that such
person is acquiring the stock subject to the Stock Award for such person's own
account and not with any present intention of selling or otherwise distributing
the stock. The foregoing requirements, and any assurances given pursuant to such
requirements, shall be inoperative if (i) the issuance of the shares upon the
exercise or acquisition of stock under the Stock Award has been registered under
a then currently effective registration statement under the Securities Act, or
(ii) as to any particular requirement, a determination is made by counsel for
the Company that such requirement need not be met in the circumstances under the
then applicable securities laws. The Company may require the holder of the Stock
Award to

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provide such other representations, written assurances or information which the
Company shall determine is necessary, desirable or appropriate to comply with
applicable securities and other laws as a condition of granting a Stock Award to
such person or permitting the holder of the Stock Award to exercise the Stock
Award. The Company may, upon advice of counsel to the Company, place legends on
stock certificates issued under the Plan as such counsel deems necessary or
appropriate in order to comply with applicable securities laws, including, but
not limited to, legends restricting the transfer of the stock.

         (e) To the extent provided by the terms of a Stock Award Agreement, the
person to whom a Stock Award is granted may satisfy any federal, state or local
tax withholding obligation relating to the exercise or acquisition of stock
under a Stock Award by any of the following means or by a combination of such
means: (1) tendering a cash payment; (2) authorizing the Company to withhold
shares from the shares of Common Stock otherwise issuable to the participant as
a result of the exercise or acquisition of stock under the Stock Award; or (3)
delivering to the Company owned and unencumbered shares of Common Stock.

11. ADJUSTMENTS UPON CHANGES IN STOCK.

         (a) If any change is made in the stock subject to the Plan, or subject
to any Stock Award, without the receipt of consideration by the Company (through
merger, consolidation, reorganization, recapitalization, reincorporation, stock
dividend, dividend in property other than cash, stock split, liquidating
dividend, combination of shares, exchange of shares, change in corporate
structure or other transaction not involving the receipt of consideration by the
Company), the Plan will be appropriately adjusted in the class(es) and maximum
number of shares subject to the Plan and the maximum number of shares subject to
award to any person during any calendar year, and the outstanding Stock Awards
will be appropriately adjusted in the class(es) and number of shares and price
per share of stock subject to such outstanding Stock Awards. Such adjustments
shall be made by the Board or Committee, the determination of which shall be
final, binding and conclusive. (The conversion of any convertible securities of
the Company shall not be treated as a "transaction not involving the receipt of
consideration by the Company.")

         (b) In the event of a Change in Control, (i) any surviving or acquiring
corporation shall assume Stock Awards outstanding under the Plan or shall
substitute similar Stock Awards for those outstanding under the Plan, or (ii) in
the event any surviving or acquiring corporation refuses to assume such Stock
Awards or to substitute similar Stock Awards for those outstanding under the
Plan, (A) with respect to Stock Awards held by persons then performing services
as Employees or Consultants, the vesting of such Stock Awards and the time
during which such Stock Awards may be exercised shall be accelerated prior to
such event and the Stock Awards terminated if not exercised after such
acceleration and at or prior to such event, and (B) with respect to any other
Stock Awards outstanding under the Plan, such Stock Awards shall be terminated
if not exercised prior to such event.

         In addition, with respect to any person who was providing services as
an Employee or Consultant immediately prior to the consummation of the Change in
Control, any Stock Awards held by such persons shall immediately become fully
vested and exercisable, and any repurchase

                                       9.
<PAGE>   10
right by the Company with respect to shares acquired by such person under a
Stock Award shall lapse, if such person's Continuous Status as an Employee or
Consultant is terminated other than for Cause within twelve (12) months
following consummation of the Change in Control. For purposes of the Plan,
"Cause" shall mean willful conduct that is materially injurious to the business
of the person's employer, whether financial or otherwise.

         For purposes of this Plan, "Change in Control" means: (1) a
dissolution, liquidation, or sale of all or substantially all of the assets of
the Company; (2) a merger or consolidation in which the Company is not the
surviving corporation; (3) a reverse merger in which the Company is the
surviving corporation but the shares of the Company's common shares outstanding
immediately preceding the merger are converted by virtue of the merger into
other property, whether in the form of securities, cash or otherwise; or (4) the
acquisition by any person, entity or group within the meaning of Section 13(d)
or 14(d) of the Exchange Act, or any comparable successor provisions (excluding
any employee benefit plan, or related trust, sponsored or maintained by the
Company or any Affiliate of the Company) of the beneficial ownership (within the
meaning of Rule 13d-3 promulgated under the Exchange Act, or comparable
successor rule) of securities of the Company representing at least fifty percent
(50%) of the combined voting power entitled to vote in the election of
directors.

12. AMENDMENT OF THE PLAN AND STOCK AWARDS.

         (a) The Board at any time, and from time to time, may amend the Plan.

         (b) The Board, in its sole discretion, may submit the Plan and/or any
amendment to the Plan for stockholder approval.

         (c) It is expressly contemplated that the Board may amend the Plan in
any respect the Board deems necessary or advisable to provide those eligible
with the maximum benefits provided or to be provided under the provisions of the
Code and the regulations promulgated thereunder.

         (d) Rights and obligations under any Stock Award granted before
amendment of the Plan shall not be impaired by any amendment of the Plan unless
(i) the Company requests the consent of the person to whom the Stock Award was
granted and (ii) such person consents in writing.

         (e) The Board at any time, and from time to time, may amend the terms
of any one or more Stock Award; provided, however, that the rights and
obligations under any Stock Award shall not be impaired by any such amendment
unless (i) the Company requests the consent of the person to whom the Stock
Award was granted and (ii) such person consents in writing.

13. TERMINATION OR SUSPENSION OF THE PLAN.

         (a) The Board may suspend or terminate the Plan at any time. Unless
sooner terminated, the Plan shall terminate on April 30, 2007, which shall be
within ten (10) years from

                                       10.
<PAGE>   11
the date the Plan is adopted by the Board. No Stock Awards may be granted under
the Plan while the Plan is suspended or after it is terminated.

         (b) Rights and obligations under any Stock Award granted while the Plan
is in effect shall not be impaired by suspension or termination of the Plan,
except with the written consent of the person to whom the Stock Award was
granted.

14. EFFECTIVE DATE OF PLAN.

         The Plan shall become effective on May 1, 1997.


                                       11.
<PAGE>   12
                             STOCK OPTION AGREEMENT


         Pursuant to the Grant Notice and this Stock Option Agreement, the
Company has granted you an option to purchase the number of shares of the
Company's common stock ("Common Stock") indicated in the Grant Notice at the
exercise price indicated in the Grant Notice.

         Your option is granted in connection with and in furtherance of the
Company's compensatory benefit plan for the Company's non-officer employees and
consultants. Defined terms not explicitly defined in this Stock Option Agreement
but defined in the Plan shall have the same definitions as in the Plan.

         The details of your option are as follows:

         1. VESTING. Subject to the limitations contained herein, your option
will vest as provided in the Grant Notice, provided that vesting will cease upon
the termination of your Continuous Status as an Employee or Consultant.

         2. METHOD OF PAYMENT.

                  (a) PAYMENT OPTIONS. Payment of the exercise price by cash or
check is due in full upon exercise of all or any part of your option, provided
that you may elect, to the extent permitted by applicable law and the Grant
Notice, to make payment of the exercise price under one of the following
alternatives:

                                  (i) Payment pursuant to a program developed
under Regulation T as promulgated by the Federal Reserve Board which, prior to
the issuance of Common Stock, results in either the receipt of cash (or check)
by the Company or the receipt of irrevocable instructions to pay the aggregate
exercise price to the Company from the sales proceeds;

                                  (ii) Provided that at the time of exercise the
Company's Common Stock is publicly traded and quoted regularly in the Wall
Street Journal, payment by delivery of already-owned shares of Common Stock,
held for the period required to avoid a charge to the Company's reported
earnings, and owned free and clear of any liens, claims, encumbrances or
security interests, which Common Stock shall be valued at its fair market value
on the date of exercise; or

                                  (iii) Payment by a combination of the above
methods.

         3. WHOLE SHARES. Your option may only be exercised for whole shares.

         4. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary
contained herein, your option may not be exercised unless the shares issuable
upon exercise of your option are then registered under the Securities Act of
1933, as amended (the "Securities
<PAGE>   13
Act") or, if such shares are not then so registered, the Company has determined
that such exercise and issuance would be exempt from the registration
requirements of the Securities Act.

         5. TERM. The term of your option commences on the Date of Grant and
expires upon the earliest of:

                                  (i) the Expiration Date indicated in the Grant
Notice;

                                  (ii) the tenth (10th) anniversary of the Date
of Grant;

                                  (iii) twelve (12) months after your death, if
you die during, or within three (3) months after the termination of your
Continuous Status as Employee or Consultant;

                                  (iv) twelve (12) months after the termination
of your Continuous Status as Employee or Consultant due to disability;

                                  (v) immediately after the termination of your
Continuous Status as Employee or Consultant for Cause; or

                                  (vi) three (3) months after the termination of
your Continuous Status as an Employee or Consultant for any other reason,
provided that if during any part of such three (3)-month period the option is
not exercisable solely because of the condition set forth in paragraph 4
(Securities Law Compliance), in which event the option shall not expire until
the earlier of the Expiration Date or until it shall have been exercisable for
an aggregate period of three (3) months after the termination of Continuous
Status as an Employee or Consultant.

                  For these purposes, "Cause" shall mean any willful conduct
that is materially injurious to the business of the person's employer, whether
financial or otherwise.

         6.  EXERCISE.

                  (a) You may exercise the vested portion of your option during
its term by delivering a notice of exercise (in a form designated by the
Company) together with the exercise price to the Secretary of the Company, or to
such other person as the Company may designate, during regular business hours,
together with such additional documents as the Company may then require.

                  (b) By exercising your option you agree that as a condition to
any exercise of your option, the Company may require you to enter an arrangement
providing for the payment by you to the Company of any tax withholding
obligation of the Company arising by reason of (1) the exercise of your option;
(2) the lapse of any substantial risk of forfeiture to which the shares are
subject at the time of exercise; or (3) the disposition of shares acquired upon
such exercise.


                                       2.
<PAGE>   14
         7. TRANSFERABILITY. Your option is not transferable, except by will or
by the laws of descent and distribution, and is exercisable during your life
only by you. Notwithstanding the foregoing, by delivering written notice to the
Company, in a form satisfactory to the Company, you may designate a third party
who, in the event of your death, shall thereafter be entitled to exercise your
option.

         8. OPTION NOT A SERVICE CONTRACT. Your option is not an employment
contract and nothing in your option shall be deemed to create in any way
whatsoever any obligation on your part to continue in the employ of the Company,
or of the Company to continue your employment with the Company. In addition,
nothing in your option shall obligate the Company, its shareholders, board of
directors, officers or employees to continue any relationship which you might
have as a consultant for the Company.

         9. NOTICES. Any notices provided for in your option or the Plan shall
be given in writing and shall be deemed effectively given upon receipt or, in
the case of notices delivered by the Company to you, five (5) days after deposit
in the United States mail, postage prepaid, addressed to you at the last address
you provided to the Company.

         10. GOVERNING PLAN DOCUMENT. Your option is subject to all the
provisions of the Plan, the provisions of which are hereby made a part of your
option, including without limitation the provisions of the Plan relating to
option provisions, and is further subject to all interpretations, amendments,
rules and regulations which may from time to time be promulgated and adopted
pursuant to the Plan. In the event of any conflict between the provisions of
your option and those of the Plan, the provisions of the Plan shall control.



                                       3.
<PAGE>   15
                                 METRICOM, INC.

                            STOCK OPTION GRANT NOTICE
                    (1997 NON-OFFICER EQUITY INCENTIVE PLAN)


METRICOM, INC. (the "Company"), pursuant to its 1997 Non-Officer Equity
Incentive Plan (the "Plan"), hereby grants to Optionee an option to purchase the
number of shares of the Company's common stock set forth below. This option is
subject to all of the terms and conditions as set forth herein and in
Attachments I, II and III, which are incorporated herein in their entirety.


Optionee:                                   _________________________________
Date of Grant:                              _________________________________
Vesting Commencement Date:                  _________________________________
Shares Subject to Option:                   _________________________________
Exercise Price Per Share:                   _________________________________
Expiration Date:                            _________________________________
Type of Option:                             Nonstatutory Stock Option

         VESTING/EXERCISE SCHEDULE:         ____% vested ___ months from Vesting
                                            Commencement Date; ______ vests at
                                            the end of each month thereafter.

PAYMENT: Any or a combination of the following: (i) by cash or check, (ii)
pursuant to a Regulation T program, as set forth in the Stock Option Agreement
or (iii) delivering shares of previously-owned common stock, as set forth in the
Stock Option Agreement.

ADDITIONAL TERMS/ACKNOWLEDGEMENTS: The undersigned Optionee acknowledges receipt
of, and understands and agrees to, this Grant Notice, the Stock Option Agreement
and the Plan. Optionee further acknowledges that as of the Date of Grant, this
Grant Notice, the Stock Option Agreement and the Plan set forth the entire
understanding between Optionee and the Company regarding the acquisition of
stock in the Company and supersedes all prior oral and written agreements on
that subject with the exception of (i) options previously granted and delivered
to Optionee under the Plan, and (ii) the following agreements only:

         OTHER AGREEMENTS:   ____________________________________
                             ____________________________________
                             ____________________________________


METRICOM, INC.                    OPTIONEE:

By: _____________________         _______________________________________
                                  Signature
Title: __________________

Date: ___________________         Date: _________________________________


Attachment I:     Stock Option Agreement
Attachment II:    1997 Non-Officer Equity Incentive Plan
Attachment III:   Notice of Exercise