EXHIBIT
      10.7

     

    Original
      Issue Date: January 16, 2008

     

    $100,000

    


    14%
      SECURED DEBENTURE

    DUE
      MAY 22, 2008

    


    THIS
      DEBENTURE is one of a series of duly authorized and validly issued 14% Secured
      Debentures of Gigabeam Corporation, a Delaware corporation, (the “Company”),
      having its principal place of business at 4021 Stirrup Creek Drive, Suite 400,
      Durham, NC 27703, designated as its 14% Secured Debenture due May 22, 2008
      (this
      debenture, the “Debenture”
and,
      collectively with the other debentures of such series, the “Debentures”).

    


    FOR
      VALUE
      RECEIVED, the Company promises to pay to Midsummer Investment, Ltd. or its
      registered assigns (the “Holder”),
      or
      shall have paid pursuant to the terms hereunder, the principal sum of $100,000
      on the earlier of (i) May 22, 2008 or (ii) the date the Company receives gross
      proceeds of $2,000,000 or more, in the aggregate, in one or a series of debt
      or
      equity financings consummated after the Original Issue Date (the “Maturity
      Date”)
      or
      such earlier date as this Debenture is required or permitted to be repaid as
      provided hereunder, and to pay interest to the Holder on the aggregate and
      then
      outstanding principal amount of this Debenture in accordance with the provisions
      hereof. This Debenture is subject to the following additional
      provisions:

    


    Notwithstanding
      anything herein to the contrary, in the event of any liquidation, insolvency,
      bankruptcy, reorganization, or similar proceedings relating to the Company,
      all
      sums payable on the Senior Convertible Notes issued by the Company on January
      28, 2005 and February 1, 2005 (“Senior
      Notes”),
      shall
      first be paid in full, with interest, if any, before any cash payment is made
      upon this Debenture, and, in any such event, any cash payment which shall be
      made in respect of this Debenture shall be paid over to the holders of the
      Senior Notes for application to the payment thereof, unless and until the
      obligations under the Senior Notes (which shall mean the principal amount
      thereof an other obligations arising out of, premium, if any on, interest on,
      and any costs and expenses payable under, the Senior Notes) shall have been
      paid
      and satisfied in full.

    


    Section
      1. Definitions.
      For the
      purposes hereof, in addition to the terms defined elsewhere in this Debenture,
      (a) capitalized terms not otherwise defined herein shall have the meanings
      set
      forth in the Purchase Agreement (as defined below) and (b) the following terms
      shall have the following meanings:


    
      
         

        
        

      

      
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    “Bankruptcy
      Event”
means
      any of the following events: (a) the Company or any Significant Subsidiary
      (as
      such term is defined in Rule 1-02(w) of Regulation S-X) thereof commences a
      case
      or other proceeding under any bankruptcy, reorganization, arrangement,
      adjustment of debt, relief of debtors, dissolution, insolvency or liquidation
      or
      similar law of any jurisdiction relating to the Company or any Significant
      Subsidiary thereof; (b) there is commenced against the Company or any
      Significant Subsidiary thereof any such case or proceeding that is not dismissed
      within 60 days after commencement; (c) the Company or any Significant Subsidiary
      thereof is adjudicated insolvent or bankrupt or any order of relief or other
      order approving any such case or proceeding is entered; (d) the Company or
      any
      Significant Subsidiary thereof suffers any appointment of any custodian or
      the
      like for it or any substantial part of its property that is not discharged
      or
      stayed within 60 calendar days after such appointment; (e) the Company or any
      Significant Subsidiary thereof makes a general assignment for the benefit of
      creditors; (f) the Company or any Significant Subsidiary thereof calls a meeting
      of its creditors with a view to arranging a composition, adjustment or
      restructuring of its debts; or (g) the Company or any Significant Subsidiary
      thereof, by any act or failure to act, expressly indicates its consent to,
      approval of or acquiescence in any of the foregoing or takes any corporate
      or
      other action for the purpose of effecting any of the foregoing.

    


    “Business
      Day”
means
      any day except Saturday, Sunday, any day which shall be a federal legal holiday
      in the United States or any day on which banking institutions in the State
      of
      New York are authorized or required by law or other governmental action to
      close.

    


    “Change
      of Control Transaction”
means
      the occurrence after the date hereof of any of (i) an acquisition after the
      date
      hereof by an individual or legal entity or “group” (as described in Rule
      13d-5(b)(1) promulgated under the Exchange Act) of effective control (whether
      through legal or beneficial ownership of capital stock of the Company, by
      contract or otherwise) of in excess of 33% of the voting securities of the
      Company, or (ii) the Company merges into or consolidates with any other Person,
      or any Person merges into or consolidates with the Company and, after giving
      effect to such transaction, the stockholders of the Company immediately prior
      to
      such transaction own less than 66% of the aggregate voting power of the Company
      or the successor entity of such transaction, or (iii) the Company sells or
      transfers all or substantially all of its assets to another Person and the
      stockholders of the Company immediately prior to such transaction own less
      than
      66% of the aggregate voting power of the acquiring entity immediately after
      the
      transaction, or (iv) a replacement at one time or within a three year period
      of
      more than one-half of the members of the Company’s board of directors which is
      not approved by a majority of those individuals who are members of the board
      of
      directors on the date hereof (or by those individuals who are serving as members
      of the board of directors on any date whose nomination to the board of directors
      was approved by a majority of the members of the board of directors who are
      members on the date hereof), or (v) the execution by the Company of an agreement
      to which the Company is a party or by which it is bound, providing for any
      of
      the events set forth in clauses (i) through (iv) above.


    
      
         

        
        

      

      
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    “Debenture
      Register”
shall
      have the meaning set forth in Section 2(b).

    


    “Event
      of Default”
shall
      have the meaning set forth in Section 5.

    


    “Fundamental
      Transaction”
means
      any transaction where (A) the Company effects any merger or consolidation of
      the
      Company with or into another Person, (B) the Company effects any sale of all
      or
      substantially all of its assets in one transaction or a series of related
      transactions, (C) any tender offer or exchange offer (whether by the Company
      or
      another Person) is completed pursuant to which holders of Common Stock are
      permitted to tender or exchange their shares for other securities, cash or
      property, or (D) the Company effects any reclassification of the Common Stock
      or
      any compulsory share exchange pursuant to which the Common Stock is effectively
      converted into or exchanged for other securities, cash or property. The exchange
      offer as
      described in that certain Securities Exchange and Amendment Agreement dated
      December 28 2007, however, shall not constitute a Fundamental Transaction as
      herein defined.

    


    “Indebtedness”
means
      (a) any liabilities for borrowed money or amounts owed in excess of $25,000
      (other than trade accounts payable incurred in the ordinary course of business),
      (b) all guaranties, endorsements and other contingent obligations in respect
      of
      indebtedness of others, whether or not the same are or should be reflected
      in
      the Company’s balance sheet (or the notes thereto), except guaranties by
      endorsement of negotiable instruments for deposit or collection or similar
      transactions in the ordinary course of business; and (c) the present value
      of
      any lease payments
      in excess of $25,000 due under leases required to be capitalized in accordance
      with GAAP.

    


    “Interest
      Payment Date”
shall
      have the meaning set forth in Section 2(a).

    


    “Late
      Fees”
shall
      have the meaning set forth in Section 2(c).

    


    “Mandatory
      Default Amount”
means
      the sum of (i) 110% of the outstanding principal amount of this Debenture,
      plus
      100% of all accrued and unpaid interest hereon and (ii) all other amounts,
      costs, expenses and liquidated damages due in respect of this
      Debenture.

    


    “New
      York Courts”
shall
      have the meaning set forth in Section 6(d).

    


    “Original
      Issue Date”
means
      the date of the first issuance of the Debentures, regardless of any transfers
      of
      any Debenture and regardless of the number of instruments which may be issued
      to
      evidence such Debentures.

    


    “Permitted
      Indebtedness”
means
      (a)
      the
      existing Indebtedness
      on
      the
      Original Issue Date (as set forth in Schedule A attached hereto and incorporated
      herein by reference), (b) lease obligations and purchase money indebtedness
      of
      up to $250,000, in the aggregate, incurred in connection with the acquisition
      of
      capital assets and lease obligations with respect to newly acquired or leased
      assets and (c) Indebtedness incurred in connection with inventory or equipment
      financing of up to $5,000,000, in the aggregate.


    
      
         

        
        

      

      
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    “Permitted
      Lien”
means
      the individual and collective reference to the following: (a) Liens for taxes,
      assessments and other governmental charges or levies not yet due or Liens for
      taxes, assessments and other governmental charges or levies being contested
      in
      good faith and by appropriate proceedings for which adequate reserves (in the
      good faith judgment of the management of the Company) have been established
      in
      accordance with GAAP, (b) Liens imposed by law which were incurred in the
      ordinary course of the Company’s business, such as carriers’, warehousemen’s and
      mechanics’ Liens, statutory landlords’ Liens, and other similar Liens arising in
      the ordinary course of the Company’s business, and which (x) do not individually
      or in the aggregate materially detract from the value of such property or assets
      or materially impair the use thereof in the operation of the business of the
      Company and its consolidated Subsidiaries or (y) are being contested in good
      faith by appropriate proceedings, which proceedings have the effect of
      preventing for the foreseeable future the forfeiture or sale of the property
      or
      asset subject to such Lien, (c) Liens securing the Senior Notes and those liens
      existing on the Original Issue Date and (d) Liens relating to Permitted
      Indebtedness as set forth in clause (b) thereof.

     

    “Purchase
      Agreement”
means
      the Securities Purchase Agreement, dated as of May 22, 2007, among the Company
      and the original Holders, as amended, modified or supplemented from time to
      time
      in accordance with its terms.

    


    “Senior
      Notes”
shall
      have the meaning set forth in the third paragraph hereof.

    


    “Securities
      Act”
means
      the Securities Act of 1933, as amended, and the rules and regulations
      promulgated thereunder.

    


    “Subsidiary”
shall
      have the meaning set forth in the Purchase Agreement.

    


    “Trading
      Day”
means
      a
      day on which the New York Stock Exchange is open for business.

    


    “Trading
      Market”
means
      the following markets or exchanges on which the Common Stock is listed or quoted
      for trading on the date in question: the American Stock Exchange, the Nasdaq
      Capital Market, the Nasdaq Global Market, the Nasdaq Global Select Market,
      the
      New York Stock Exchange or the OTC Bulletin Board.

    


    Section
      2. Interest.

     

    a) Payment
      of Interest.
      The
      Company shall pay interest to the Holder on the aggregate then outstanding
      principal amount of this Debenture at the rate of 14% per annum payable on
      the
      Maturity Date (the “Interest
      Payment Date”)
      (if
      the Interest Payment Date is not a Business Day, then the applicable payment
      shall be due on the next succeeding Business Day), in cash. 

     

    
      
         

        
        

      

      
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    b) Interest
      Calculations.
      Interest shall be calculated on the basis of a 360-day year, consisting of
      twelve 30 calendar day periods, and shall accrue daily commencing on the
      Original Issue Date until payment in full of the outstanding principal, together
      with all accrued and unpaid interest, liquidated damages and other amounts
      which
      may become due hereunder, has been made. Interest hereunder will be paid to
      the
      Person in whose name this Debenture is registered on the records of the Company
      regarding registration and transfers of this Debenture (the “Debenture
      Register”).
      

    


    c) Late
      Fee.
      All
      overdue accrued and unpaid interest to be paid hereunder shall entail a late
      fee
      at an interest rate equal to the lesser of 18% per annum or the maximum rate
      permitted by applicable law (“Late
      Fees”)
      which
      shall accrue daily from the date such interest is due hereunder through and
      including the date of payment in full. 

     

    d) Prepayment.
      The
      Company may prepay any portion of the principal amount of this Debenture on
      five
      Trading Days prior written notice to the Holder. 

    


    Section
      3.  Registration
      of Transfers and Exchanges.
      

     

    a) Different
      Denominations.
      This
      Debenture is exchangeable for an equal aggregate principal amount of Debentures
      of different authorized denominations, as requested by the Holder surrendering
      the same. No service charge will be payable for such registration of
      exchange.

     

    b) Investment
      Representations.
      This
      Debenture has been issued subject to certain investment representations of
      the
      original Holder set forth in the Purchase Agreement and may be transferred
      or
      exchanged only in compliance with the Purchase Agreement and applicable federal
      and state securities laws and regulations. In the event of a transfer to any
      third party, subject to the terms of the Purchase Agreement, such transfer
      shall
      be in denominations at least equal to the lesser of $250,000 principal amount
      and the principal amount of Debentures then outstanding and held by the
      Holder.

    


    c) Reliance
      on Debenture Register.
      Prior
      to due presentment for transfer to the Company of this Debenture, the Company
      and any agent of the Company may treat the Person in whose name this Debenture
      is duly registered on the records of the Company as the owner hereof for the
      purpose of receiving payment as herein provided and for all other purposes,
      whether or not this Debenture is overdue, and neither the Company nor any such
      agent shall be affected by notice to the contrary.

    


    Section
      4. Negative
      Covenants.
      As long
      as any portion of this Debenture remains outstanding, unless the holders of
      at
      least 67% in principal amount of the then outstanding Debentures shall have
      otherwise given prior written consent, the Company shall not, and shall not
      permit any of its subsidiaries (whether or not a Subsidiary on the Original
      Issue Date) to, directly or indirectly:


    
      
         

        
        

      

      
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    a) other
      than Permitted Indebtedness, enter into, create, incur, assume, guarantee or
      suffer to exist any indebtedness for borrowed money of any kind, including
      but
      not limited to, a guarantee, on or with respect to any of its property or assets
      now owned or hereafter acquired or any interest therein or any income or profits
      therefrom;

     

    b) other
      than Permitted Liens, enter into, create, incur, assume or suffer to exist
      any
      Liens of any kind, on or with respect to any of its property or assets now
      owned
      or hereafter acquired or any interest therein or any income or profits
      therefrom;

    


    c) amend
      its
      charter documents, including, without limitation, its certificate of
      incorporation and bylaws, in any manner that materially and adversely affects
      any rights of the Holder;

    


    d) repay,
      repurchase or offer to repay, repurchase or otherwise acquire more than a
de minimis
      number
      of shares of its Common Stock or Common Stock Equivalents other than as to
      (a)
      the Warrant Shares as permitted or required under the Transaction Documents;
      (b)
      repurchases of Common Stock or Common Stock Equivalents of departing officers
      and directors of the Company, provided that such repurchases shall not exceed
      an
      aggregate of $250,000 for all officers and directors during the term of this
      Debenture; and
      (c)
      the recapitalization as described in that certain Securities Exchange and
      Amendment Agreement dated December 31 2007;

    


    e) pay
      cash
      dividends or distributions on any equity securities of the Company other than
      dividends and distributions required to be made in respect of the Series A,
      Series B, Series C and Series D preferred shares pursuant to the terms of the
      Certificates of Designation as in effect of the date hereof;

    


    f) enter
      into any transaction with any Affiliate of the Company which would be required
      to be disclosed in any public filing with the Commission, unless such
      transaction is made on an arm’s-length basis and expressly approved by a
      majority of the disinterested directors of the Company (even if less than a
      quorum otherwise required for board approval); or

    


    g) enter
      into any agreement with respect to any of the foregoing.

     

    Section
      5. Events
      of Default.
      

    


    a) “Event
      of Default”
means,
      wherever used herein, any of the following events (whatever the reason for
      such
      event and whether such event shall be voluntary or involuntary or effected
      by
      operation of law or pursuant to any judgment, decree or order of any court,
      or
      any order, rule or regulation of any administrative or governmental
      body):


    
      
         

        
        

      

      
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    i. any
      default in the payment of (A) the principal amount of any Debenture or (B)
      interest, liquidated damages and other amounts owing to a Holder on any
      Debenture, as and when the same shall become due and payable (whether on the
      Maturity Date or by acceleration or otherwise) which default, solely in the
      case
      of an interest payment or other default under clause (B) above, is not cured
      within 3 Trading Days;

     

    ii. the
      Company shall fail to observe or perform any other covenant or agreement
      contained in the Debentures which failure is not cured, if possible to cure,
      within the earlier to occur
      of
(A)
      15
Trading
      Days after notice of such failure sent by the Holder or by any other
      Holder
      and (B)
      30 Trading Days after the Company has become or should have become aware of
      such
      failure;

    


    iii. a
      default
      or event of default (subject to any grace or cure period provided in the
      applicable agreement, document or instrument) shall occur for the first time
      after January 29, 2008 under (A) any of the Transaction Documents or (B) any
      other material agreement, lease, document or instrument to which the Company
      or
      any Subsidiary is obligated (and not covered by clause (vi) below);

    


    iv. any
      representation
      or warranty made in this Debenture, any other Transaction Documents, any written
      statement pursuant hereto or thereto or any other report, financial statement
      or
      certificate made or delivered to the Holder or any other Holder shall
      be
      untrue or incorrect in any material respect as of the date when made or deemed
      made;

    


    v. the
      Company or any Significant Subsidiary shall be subject to a Bankruptcy
      Event;

     

    vi. after
      January 29, 2008, the Company or any Subsidiary shall default on any of its
      obligations incurred after January 29, 2008 under any mortgage, credit agreement
      or other facility, indenture agreement, factoring agreement or other instrument
      under which there may be issued, or by which there may be secured or evidenced,
      any indebtedness for borrowed money or money due under any long term leasing
      or
      factoring arrangement that (a) involves an obligation greater than $250,000,
      whether such indebtedness now exists or shall hereafter be created, and (b)
      results in such indebtedness becoming or being declared due and payable prior
      to
      the date on which it would otherwise become due and payable; 

    


    vii. the
      Common Stock shall not be eligible for listing or quotation for trading on
      a
      Trading Market and shall not be eligible to resume listing or quotation for
      trading thereon within five Trading Days;


    
      
         

        
        

      

      
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    viii. the
      Company shall be a party to any Change of Control Transaction or Fundamental
      Transaction or shall agree to sell or dispose of all or in excess of 33% of
      its
      assets in one transaction or a series of related transactions (whether or not
      such sale would constitute a Change of Control Transaction); or

    


    ix. any
      monetary judgment, writ or similar final process shall be entered or filed
      against the Company, any subsidiary or any of their respective property or
      other
      assets for more than $300,000, and such judgment, writ or similar final process
      shall remain unvacated, unbonded or unstayed for a period of 45 calendar
      days.

    


    b) Remedies
      Upon Event of Default.
      If any
      Event of Default occurs, the outstanding principal amount of this Debenture,
      plus accrued but unpaid interest, liquidated damages and other amounts owing
      in
      respect thereof through the date of acceleration, shall become, at the Holder’s
      election, immediately due and payable in cash at the Mandatory Default Amount.
      Commencing 5 days after the occurrence of any Event of Default that results
      in
      the eventual acceleration of this Debenture, the interest rate on this Debenture
      shall accrue at an interest rate equal to the lesser of 18% per annum or the
      maximum rate permitted under applicable law. Upon the payment in full of the
      Mandatory Default Amount, the Holder shall promptly surrender this Debenture
      to
      or as directed by the Company. In connection with such acceleration described
      herein, the Holder need not provide, and the Company hereby waives, any
      presentment, demand, protest or other notice of any kind, and the Holder may
      upon the expiration of the applicable grace period, if any, enforce any and
      all
      of its rights and remedies hereunder and all other remedies available to it
      under applicable law. Such acceleration may be rescinded and annulled by Holder
      at any time prior to payment hereunder and the Holder shall have all rights
      as a
      holder of the Debenture until such time, if any, as the Holder receives full
      payment pursuant to this Section 5(b). No such rescission or annulment shall
      affect any subsequent Event of Default or impair any right consequent
      thereon.

    


    Section
      6. Miscellaneous.
      

     

    a) Notices.
      Any and
      all notices or other communications or deliveries to be provided by the Holder
      hereunder, shall be in writing and delivered personally, by facsimile, or sent
      by a nationally recognized overnight courier service, addressed to the Company,
      at the address set forth above, or such other facsimile number or address as
      the
      Company may specify for such purpose by notice to the Holder delivered in
      accordance with this Section 6. Any and all notices or other communications
      or
      deliveries to be provided by the Company hereunder shall be in writing and
      delivered personally, by facsimile, or sent by a nationally recognized overnight
      courier service addressed to each Holder at the facsimile number or address
      of
      such Holder appearing on the books of the Company, or if no such facsimile
      number or address appears, at the principal place of business of the Holder.
      Any
      notice or other communication or deliveries hereunder shall be deemed given
      and
      effective on the earliest of (i) the date of transmission, if such notice or
      communication is delivered via facsimile at the facsimile number specified
      in
      this Section 6 prior to 5:30 p.m. (New York City time), (ii) the date
      immediately following the date of transmission, if such notice or communication
      is delivered via facsimile at the facsimile number specified in this Section
      6
      between 5:30 p.m. (New York City time) and 11:59 p.m. (New York City time)
      on
      any date, (iii) the second Business Day following the date of mailing, if sent
      by nationally recognized overnight courier service, or (iv) upon actual receipt
      by the party to whom such notice is required to be given.


    
      
         

        
        

      

      
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    b) Absolute
      Obligation.
      Except
      as expressly provided herein, no provision of this Debenture shall alter or
      impair the obligation of the Company, which is absolute and unconditional,
      to
      pay the principal of, liquidated damages and accrued interest, as applicable,
      on
      this Debenture at the time, place, and rate, and in the coin or currency, herein
      prescribed. This Debenture is a direct debt obligation of the Company. This
      Debenture ranks pari passu
      with all
      other Debentures now or hereafter issued under the terms set forth
      herein.  

     

    c) Lost
      or Mutilated Debenture.
      If this
      Debenture shall be mutilated, lost, stolen or destroyed, the Company shall
      execute and deliver, in exchange and substitution for and upon cancellation
      of a
      mutilated Debenture, or in lieu of or in substitution for a lost, stolen or
      destroyed Debenture, a new Debenture for the principal amount of this Debenture
      so mutilated, lost, stolen or destroyed, but only upon receipt of evidence
      of
      such loss, theft or destruction of such Debenture, and of the ownership hereof,
      reasonably satisfactory to the Company.

    


    d) Governing
      Law.
      All
      questions concerning the construction, validity, enforcement and interpretation
      of this Debenture shall be governed by and construed and enforced in accordance
      with the internal laws of the State of New York, without regard to the
      principles of conflict of laws thereof. Each party agrees that all legal
      proceedings concerning the interpretation, enforcement and defense of the
      transactions contemplated by any of the Transaction Documents (whether brought
      against a party hereto or its respective Affiliates, directors, officers,
      shareholders, employees or agents) shall be commenced in the state and federal
      courts sitting in the City of New York, Borough of Manhattan (the “New
      York Courts”).
      Each
      party hereto hereby irrevocably submits to the exclusive jurisdiction of the
      New
      York Courts for the adjudication of any dispute hereunder or in connection
      herewith or with any transaction contemplated hereby or discussed herein
      (including with respect to the enforcement of any of the Transaction Documents),
      and hereby irrevocably waives, and agrees not to assert in any suit, action
      or
      proceeding, any claim that it is not personally subject to the jurisdiction
      of
      such New York Courts, or such New York Courts are improper or inconvenient
      venue
      for such proceeding. Each party hereby irrevocably waives personal service
      of
      process and consents to process being served in any such suit, action or
      proceeding by mailing a copy thereof via registered or certified mail or
      overnight delivery (with evidence of delivery) to such party at the address
      in
      effect for notices to it under this Debenture and agrees that such service
      shall
      constitute good and sufficient service of process and notice thereof. Nothing
      contained herein shall be deemed to limit in any way any right to serve process
      in any other manner permitted by applicable law. Each party hereto hereby
      irrevocably waives, to the fullest extent permitted by applicable law, any
      and
      all right to trial by jury in any legal proceeding arising out of or relating
      to
      this Debenture or the transactions contemplated hereby. If either party shall
      commence an action or proceeding to enforce any provisions of this Debenture,
      then the prevailing party in such action or proceeding shall be reimbursed
      by
      the other party for its attorneys’ fees and other costs and expenses incurred in
      the investigation, preparation and prosecution of such action or
      proceeding.

     

    
      
         

        
        

      

      
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    e) Waiver.
      Any
      waiver by the Company or the Holder of a breach of any provision of this
      Debenture shall not operate as or be construed to be a waiver of any other
      breach of such provision or of any breach of any other provision of this
      Debenture. The failure of the Company or the Holder to insist upon strict
      adherence to any term of this Debenture on one or more occasions shall not
      be
      considered a waiver or deprive that party of the right thereafter to insist
      upon
      strict adherence to that term or any other term of this Debenture. Any waiver
      by
      the Company or the Holder must be in writing.

     

    f) Severability.
      If any
      provision of this Debenture is invalid, illegal or unenforceable, the balance
      of
      this Debenture shall remain in effect, and if any provision is inapplicable
      to
      any Person or circumstance, it shall nevertheless remain applicable to all
      other
      Persons and circumstances. If it shall be found that any interest or other
      amount deemed interest due hereunder violates the applicable law governing
      usury, the applicable rate of interest due hereunder shall automatically be
      lowered to equal the maximum rate of interest permitted under applicable law.
      The Company covenants (to the extent that it may lawfully do so) that it shall
      not at any time insist upon, plead, or in any manner whatsoever claim or take
      the benefit or advantage of, any stay, extension or usury law or other law
      which
      would prohibit or forgive the Company from paying all or any portion of the
      principal of or interest on this Debenture as contemplated herein, wherever
      enacted, now or at any time hereafter in force, or which may affect the
      covenants or the performance of this indenture, and the Company (to the extent
      it may lawfully do so) hereby expressly waives all benefits or advantage of
      any
      such law, and covenants that it will not, by resort to any such law, hinder,
      delay or impeded the execution of any power herein granted to the Holder, but
      will suffer and permit the execution of every such as though no such law has
      been enacted.

     

    g) Next
      Business Day.
      Whenever any payment or other obligation hereunder shall be due on a day other
      than a Business Day, such payment shall be made on the next succeeding Business
      Day.

    


    h) Headings.
      The
      headings contained herein are for convenience only, do not constitute a part
      of
      this Debenture and shall not be deemed to limit or affect any of the provisions
      hereof.


    
      
         

        
        

      

      
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    i) Assumption. 
      Any successor to the Company or any surviving entity in a Fundamental
      Transaction shall (i) assume, prior to such Fundamental Transaction, all of
      the
      obligations of the Company under this Debenture and the other Transaction
      Documents pursuant to written agreements in form and substance satisfactory
      to
      the Holder (such approval not to be unreasonably withheld or delayed) and (ii)
      issue to the Holder a new debenture of such successor entity evidenced by a
      written instrument substantially similar in form and substance to this
      Debenture, including, without limitation, having a principal amount and interest
      rate equal to the principal amount and the interest rate of this Debenture
      and
      having similar ranking to this Debenture, which shall be satisfactory to the
      Holder (any such approval not to be unreasonably withheld or delayed).  The
      provisions of this Section 6(i) shall apply similarly and equally to successive
      Fundamental Transactions and shall be applied without regard to any limitations
      of this Debenture.


    
      
         

        
        

      

      
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    j) Secured
      Obligation.
      The
      obligations of the Company under this Debenture are secured by certain assets
      of
      the Company and each Subsidiary pursuant to the Security Agreement, dated as
      of
      May 22, 2007 between the Company, the Subsidiaries of the Company and the
      Secured Parties (as defined therein).

    


    *********************


    
      
         

        
        

      

      
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    IN
      WITNESS WHEREOF, the Company has caused this Debenture to be duly executed
      by a
      duly authorized officer as of the date first above indicated.

     

    
      	 	
              GIGABEAM
                CORPORATION

            	 
	 	 	 
	 	
              By:

            	
              /s/
                S. Jay Lawrence

            	 
	 	 	
              Name:
                S. Jay Lawrence

              Title:
                Chief Executive Officer

            	 
	 	
              Facsimile
                No. for delivery of Notices:
                _______________

            


    

     

    
      
         

        
        

      

      
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