Exhibit 10.66
  SENIOR
SECURED PROMISSORY NOTE
  $
      128,319.10
                March 24,
    2010Sarasota,
      Florida
 
 FOR VALUE
RECEIVED, the undersigned, INVISA, INC., a Nevada
corporation (“Borrower”)
having an address at 1800 2nd
Street, Suite 965, , Sarasota, Florida, 34236 promises to pay to the order of
Centurian Investors, Inc, a Delaware corporation (“Lender”),
having an office at 1800 2nd
Street, Suite 970, Sarasota, Florida 34236, or such other place as the Lender
may designate in writing, the principal amount up to and not to exceed ONE
HUNDRED TWENTY EIGHT THOUSAND THREE HUNDRED NINETEEN United States Dollars and
TEN cents (U.S. $128,319.10), to the extent advanced hereunder and then
outstanding, with interest on the unpaid principal balance from the date of this
Senior Secured Promissory Note (this “Promissory
Note”), until paid, at the Interest Rate (as hereinafter defined)
provided herein.
  1.           Rate of
Interest.  The outstanding principal balance of this Promissory
Note shall bear interest at ten percent (10%) per annum (the “Interest
Rate”).
  2.           Date and
Time of Payment.  The outstanding principal balance of this
Promissory Note, together with all accrued and unpaid interest,  shall
be paid in full on earlier to occur of (a) the Maturity Date or (b) the date of
termination of this Promissory Note, whether by its terms, by prepayment, or by
acceleration.  All amounts outstanding hereunder shall constitute
Borrower’s obligations hereunder, and such obligations include without
limitation all principal, interest (including all interest which accrues after
the commencement of any case or proceeding by or against Borrower in bankruptcy
whether or not allowed in such case or proceeding), expenses, attorneys’ fees
and any other sum chargeable to Borrower hereunder and owing to Lender under
this Promissory Note (all such obligations and all other obligations of Borrower
under this Promissory Note ,(the “Obligations”).
  3.           Default
Rate.  Notwithstanding Section 1, after the
occurrence of any Event of Default and for so long as such Event of Default
continues, and in any event from and after the Maturity Date, all principal,
interest and other amounts payable under this Promissory Note shall bear
interest until paid in full at a rate of interest equal to four percent (4%)
above the per annum rate otherwise applicable hereunder (the “Default
Rate”).
  4.           Computation
of Interest.  Interest on the principal amount hereof and all
other Obligations shall be computed on the basis of a 360-day year, and shall be
charged for the actual number of days elapsed during any month or other accrual
period.
  5.           Manner of
Payment.  All payments by Borrower in respect of any
Obligations shall be made without deduction, defense, set off or counterclaim,
free and clear of all taxes delivered to Lender.
  6.           Maturity.  To
the extent not sooner due and payable in accordance with this Promissory Note,
the Obigations  shall be due and payable on  March 1, 2012
(the “Maturity
Date”).
  1
 
 7.           Application
of Payments.  All payments shall be applied to amounts then due
and payable in the following order:  (a) to Lender’s costs and
expenses reimbursable in connection herewith; (b) to interest accrued on the
outstanding principal balance of this Promissory Note; (c) to the principal
amount hereof; and (d) to all other Obligations, or in such other manner as
Lender shall determine in its sole and exclusive discretion.
  8.           [Intentionally
Deleted]
  9.           Security.  This Promissory
Note shall be secured by (i) Seventeen Million, Sixty Six Thousand Six Hundred
Sixty Eight (17,066,668) shares of common stock of Borrower to be issued as of
the date hereof or when available, or the equivilant thereof, in a form of
preferred stock or other security to be designated by Borrower  with
such terms and conditions as are acceptable to the Lender, and held in escrow
and a continuing first priority security interest in all of Borrower’s right,
title, and interest in and to, all property of Borrower (collectively, the
“Collateral”),
as more specifically set forth in the Security Agreement executed by Borrower in
favor of Lender dated as of February 28, 2007.  (the “Security
Agreement”).
  10.          PriorityThis Promissory Note
shall be a senior obligation of Borrower, and for so long as this Promissory
Note shall be outstanding, (i) Borrower shall be prohibited from incurring any
and all future indebtedness without the prior written consent of Lender and (ii)
any and all future indebtedness approved by Borrower in writing shall be deemed
subordinate and inferior to, all respective right, title and interest of Lender,
in, to and under this Promissory Note, this Security Agreement and any and all
documents and instruments evidencing, securing or otherwise relating to this
Promissory Note.
  11.         Representations
and Warranties.Borrower makes
the following representations and warranties to Lender, which representations
and warranties shall be true, correct, and complete as of the date hereof and
shall survive the execution and delivery of this Promissory Note.
  (a)         Due
Organization and Qualification.  Borrower is duly organized and
validly existing and in good standing under the laws of the jurisdiction of its
organization and qualified to do business in any jurisdiction where it is
required to be so qualified, and has all requisite power and authority to (i)
own its assets and carry on its business, and (ii) execute, deliver and perform
its Obligations.
  (b)         Due
Authorization; No Conflict.  The execution, delivery, and
performance by Borrower of this Promissory Note has been duly authorized by all
necessary action on the part of Borrower.  This Promissory Note has
been duly executed and delivered by Borrower.  The execution,
delivery, and performance by Borrower of this Promissory Note and the
consummation of the transactions contemplated hereby, do not and will not (i)
violate in any material respect any provision of federal, state, provincial or
local law or regulation applicable to Borrower, its organizational documents, or
any order, judgment, or decree of any court or other governmental authority,
(ii) conflict with, result in a breach or termination of, or constitute (with
due notice or lapse of time or both) a default under any material contractual
obligation of Borrower, (iii) result in or require the creation or imposition of
any lien of any nature whatsoever upon any properties or assets of Borrower,
other than liens or security interests in favor of Lender, or (iv) require any
approval of any of Borrower’s stockholders or any approval or consent of any
other person or entity, other than consents or approvals that have been obtained
and that are still in force and effect.  The execution, delivery, and
performance by Borrower of this Promissory Note do not and will not require any
registration with, consent, or approval of, or notice to, or other action with
or by, any governmental authority, other than consents or approvals that have
been obtained and that are still in force and effect.  This Promissory
Note when executed and delivered by Borrower will be the legally valid and
binding obligation of Borrower, enforceable against Borrower in accordance with
its term, except as enforcement may be limited by equitable principles or by
bankruptcy, insolvency, reorganization, moratorium, or similar laws relating to
or limiting creditors’ rights generally.
  2
  (c)         No Litigation.  No
litigation, investigation or proceeding of or before any arbitrator or
government authority is (i) pending or, to the knowledge of Borrower, threatened
with respect to this Promissory Note or the Collateral or any of the
transactions contemplated hereby or (ii) pending or, to the knowledge of
Borrower, threatened by or against Borrower, its properties or revenues which,
if adversely determined, would have a material adverse effect on its business,
operations, property or financial condition, when taken as a whole.
  (d)        No
Default.  Borrower is not in default under or with respect to
any contractual obligation and no event of default has occurred or is continuing
with respect to Borrower.
  (e)        Taxes.  Borrower has
filed or caused to be filed all tax returns required to be filed by it and has
paid all taxes due and payable on said returns or on any assessments made
against Borrower or any of its property.   All other taxes, fees
or other charges on Borrower or any of its property by any governmental
authority have been paid and no tax liens have been filed.
  12.  Covenants
of Borrower.As of the date hereof and so long as the
Obligations hereunder shall be outstanding:
  (a)  Borrower will preserve
and keep in force and effect, its corporate existence and all licenses and
permits necessary to the proper conduct of its business;
 
 (b)  Borrower will promptly
pay and discharge, all lawful taxes, assessments, charges or levies imposed upon
Borrower, or upon or in respect of all or any part of the property or business
of Borrower, all trade accounts payable in accordance with usual and customary
business terms and all claims for work, labor or materials, which if unpaid
might become a lien or charge upon any property of Borrower; provided, Borrower
shall not be required to pay such tax, assessment, charge, levy, account payable
or claim if (i) the validity, applicability or amount thereof is being contested
in good faith by appropriate action or proceeding which will prevent the
forfeiture or sale of any property of Borrower, and (ii) Borrower shall set
aside on its books, reserves deemed by it to be adequate with respect
thereto;
 
 (c)  Borrower will promptly
comply with all laws, ordinances or governmental rules and regulation to which
it is subject, the violations of which would materially or adversely affect its
properties, business, prospects, profits or condition or would result in any
material lien or charge upon any property of Borrower;
  3
  (d)  Borrower will maintain,
preserve and keep its properties which are used or useful in the conduct of its
business in good repair and working order;
 
 (e)  Borrower will not
create, assume or incur or in any manner become liable with respect of any
indebtedness except this Promissory Note and any indebtedness of Borrower
incurred prior to the date hereof.
 
 (f)  Borrower will not create
or incur any mortgage, pledge, security interest, encumbrance, lien or charge of
any kind (a “Lien”) on its or its property or assets, whether now owned or
hereinafter acquired, or upon any income or profits
therefrom  except
 
 (i)           Liens
for property taxes and assessments or levies and liens that are not yet due and
payable;
 
 (ii)          Liens
of or resulting from any judgment or award, the time for appeal or petition for
rehearing of which shall not have expired or in respect of which the Company
shall in good faith be prosecuting an appeal or proceeding for a review and in
respect of which a stay of execution pending such appeal or proceeding for
review shall have been secured; or
 
 (iii)         Liens
or priority claims (A) incidental to the conduct of business, (B) created by any
material agreement of Borrower entered into prior to and currently in effect as
of the date hereof or (C) the ownership or lease of properties and assets and
not in connection with the borrowing of money, provided, in each
case, the obligation secured is not overdue, or if overdue, is being contested
in good faith by appropriate actions or proceedings and provided, furtherthat Borrower
shall have received the prior written consent of Lender to any Lien described in
(A) or (C) above; or
 
 13.          Events of
Default; Remedies; Acceleration.  (a) The occurrence of any one
or more of the following events (regardless of the reason therefor) shall
constitute an “Event of
Default” hereunder:
  (i) Borrower fails to make any payment of outstanding principal balance of this
Promissory Note , or interest thereon, or any of the other Obligation when due
and payable;
  (ii) Any representation or warranty of Borrower made in this Promissory
Note, the Security Agreeent,  or any other document made by or on
behalf of Borrower in connection herewith and the transactions contemplated
hereby proves to have been false or incorrect in any material respect or
Borrower shall fail to comply in all respects with any covenant herein or
therein;
  (iii) Borrower shall violate any
provision of this Promissory Note, the Security Agreement or any other document
made by or on behalf of Borrower in connection herewith and the transactions
contemplated hereby, including, without limitiation, failure to comply with the
terms and provisions of Section 8 of this Promissory Note;
  4
 
 (iv) A case or proceeding is commenced against Borrower seeking a decree
or order (i) under Title 11 of the United States Bankruptcy Code (11 U.S.C.
§§101 et seq., as
amended, and any successor statute, the “Bankruptcy
Code”), or any other applicable federal, state or foreign bankruptcy or
other similar law, rule or regulation, (ii) appointing a custodian, receiver,
liquidator, assignee, trustee or sequestrator (or similar official) for Borrower
or for any substantial part of Borrower’s assets, or (iii) ordering the
winding-up or liquidation of the affairs of s Borrower, and such case or
proceeding shall remain undismissed or unstayed for sixty (60) days or more or a
decree or order granting the relief sought in such case or proceeding shall be
entered by a court of competent jurisdiction;
  (v) Borrower, without the prior written consent of Lender (A) files a
petition seeking relief under the Bankruptcy Code, or any other applicable
federal, state or foreign bankruptcy or other similar law, rule or regulation,
(B) consents to or fails to contest in a timely and appropriate manner the
institution of proceedings thereunder or the filing of any such petition or the
appointment of or taking possession by a custodian, receiver, liquidator,
assignee, trustee or sequestrator (or similar official) for Borrower or for any
substantial part of Borrower’s assets, (C) makes an assignment for the benefit
of creditors, (D) takes any action in furtherance of any of the foregoing; or
(E) admits in writing its inability to, or is generally unable to, pay its debts
as such debts become due;
  (vi)  If this Promissory Note, the Security Agreement, or any
financing statement, document or other instrument executed, delivered or filed
in connection herewith or with the security interest granted to Lender
hereunder, shall, for any reason, fail or cease to create a valid and perfected
lien on or security interest in any or all of the Collateral or the Collateral
shall be compromised, encumbered or, in the case of the common stock, invalid,
cancelled or otherwise rescinded;
  (vi) If
Borrower shall default on any material obligations of Borrower or an event of
default shall occur with respect to any material agreement of Borrower, whether
such agreement shall be in effect or effective subsequent to this Promissory
Note.
  (b)       
 Immediately upon the occurrence of any Event of Default, Lender may (i) proceed to protect and
enforce Lender’s rights by suit in equity, action at law and/or other
appropriate proceeding, either for specific performance of any covenant or
condition contained in this Promissory Note, the Security Agreement, or in any
instrument or document delivered to Lender pursuant to this Promissory Note , or
in aid of the exercise of any power granted in this Promissory Note or any such
instrument or document, and (ii) proceed to enforce payment of the Obligations
in such manner as Lender may elect,including the foreclosure of the Collateral in
accordance with the terms of the Security Agreement, and to realize upon
any and all rights of Lender hereunder.  Upon the occurrence of any
Event of Default under Section 13(a)(iv) and (v), Lender shall have a right to
immediately enforce its rights hereunder and proceed against or foreclose upon
the Collateral without regard to the 45 day period set forth in this Section
13(b) To the extent not prohibited by applicable law which cannot be waived, all
of Lender’s rights hereunder shall be cumulative.  Lender shall have
all other rights and remedies not inconsistent herewith as provided under
applicable law or in equity, and no exercise by Lender of one right or remedy
shall be deemed an election, and no waiver by Lender of any Event of Default
shall be deemed a continuing waiver.   No delay by Lender shall
constitute a waiver, election or acquiescence by it.
  5
 (c) In the event that the Obligations
hereunder shall be paid in full by or on behalf of Borrower, after the
Acceleration of this Promissory Note but prior to the Final Payment Date, then
this Promissory Note shall be deemed paid in full, Lender shall promptly release
any lien of Lender on the Collateral, and each Lender Nominee shall immediately
resign from the Board of Directors of Borrower.
  14.     
  CertainRights
and Waivers.  To the extent not prohibited by the provisions of
applicable law, Borrower hereby expressly waives: (a) all presentments, demands
for performance, notices of nonperformance (except to the extent required by
this Note), protests, notices of protest and notices of dishonor; (b) any
requirement of diligence or promptness on the part of Lender in the enforcement
of its rights under this Note; (c) any and all notices of every kind and
description which may be required to be given by any statute or rule of law; and
(d) any defense (other than indefeasible payment in full) which it may now or
hereafter have with respect to its liability under this Note.
 
 15.          Assignments.  Borrower
may not assign or transfer any of its rights or obligations hereunder without
the express, written consent of Lender.  Any such purported assignment
or transfer by Borrower without the express, written consent of Lender shall be
null and void ab
initio.
   16.          Costs and
Expenses.  Borrower agrees to pay all costs and expenses of
Lender, including without limitation all fees and disbursements of counsel,
advisors, consultants, examiners and appraisers for Lender, in connection with
(a) the issuance of this Promissory Note and advancement of principal amount
hereunder (which fees and disbursements associated with the origination of this
Promissory Note shall not exceed $3,500.00), (b) any enforcement (whether
through negotiations, legal process or otherwise) of this Promissory Note, (c)
any workout or restructuring of this Promissory Note during the pendency of one
or more Events of Default, (d) any bankruptcy case or proceeding of Borrower or
any appeal thereof, and (e) upon the occurrence and during the continuance of an
Event of Default, any efforts to verify, protect, evaluate, assess, appraise,
collect, sell, liquidate or otherwise dispose of any of the
Collateral.
  6
 
 17.        CHOICE OF
LAW.  THE VALIDITY OF THIS NOTE, THE
CONSTRUCTION, INTERPRETATION, AND ENFORCEMENT HEREOF, AND THE RIGHTS OF THE
BORROWER AND LENDER WITH RESPECT TO ALL MATTERS ARISING HEREUNDER OR RELATED
HERETO SHALL BE DETERMINED UNDER, GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF FLORIDA, WITHOUT REFERENCE TO CONFLICTS OF LAW
PRINCIPLES EXCEPT TO THE EXTENT NECESSARY TO ENFORCE THIS CHOICE OF LAW
PROVISION.
  18.Notices.  All
communications hereunder shall be in writing and shall be deemed to be duly
given and received (a) upon delivery if delivered personally or upon confirmed
transmittal if by facsimile, (b) on the next Business Day if sent by
overnight courier, or (c) four (4) Business Days after mailing if mailed by
prepaid registered mail, return receipt requested, in each case to the
appropriate notice address or facsimile number.
  19.  Independent
Arms Length Transaction.  It is understood and agreed that this
Promissory Note, the Security Agreement and the transactions contemplated hereby
and thereby were negotiated in an arms length transacton separate and distinct
from any other transaction or contractual obligations and are independent of any
transaction or transactions between Borrower, on the one hand, and Lender and
any of its affilates or related entitles on the other
hand.   Borrower further agrees that the contractual obligations
of Borrower hereunder are in no way dependent or conditioned upon any other
agreements, contracts or transactions whatsoever unless expressly stated
herein.
    7
  IN
WITNESS WHEREOF, the undersigned has executed this Promissory Note as of the
date first written above.
  INVISA,
      INC.
                
                By:  __________________________
                Name:Edmund
      C. King
                Title:Chief
      Financial Officer