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                                                                    EXHIBIT 10.8

THIS NOTE AND THE COMMON STOCK THAT MAY BE ISSUED UPON ITS CONVERSION HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES
LAWS OF ANY STATE AND MAY NOT BE SOLD, TRANSFERRED, OR PLEDGED IN THE ABSENCE OF
AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND STATUTES OR, UNLESS PRIOR
TO ANY SALE, TRANSFER, OR PLEDGE, THE ISSUER RECEIVES AN OPINION OF COUNSEL, IN
FORM AND SUBSTANCE SATISFACTORY TO IT, THAT REGISTRATION IS NOT REQUIRED UNDER
SUCH ACT AND STATUTES AND THE RULES PROMULGATED THEREUNDER.

                      CONVERTIBLE, STRAIGHT PROMISSORY NOTE

$1,000,000.00                                                    August 27, 2001


         For value received, the undersigned, CETALON CORPORATION, a Nevada
corporation (the "Company") hereby promises to pay to the order of NATURE'S
SUNSHINE PRODUCTS, INC., a Utah corporation, its successors and assigns (the
"Holder"), in lawful money of the United States of America, the principal sum of
One Million and no/100ths Dollars ($1,000,000.00) and all interest accrued
thereon. Interest shall accrue on any unpaid principle balance of this Note on a
daily basis at the rate of twelve percent (12%) per annum, compounded annually,
and shall be calculated on the basis of a 365-day year.

                              Terms and Conditions

         1. Term of Loan. Principal and all accrued interest under this Note
shall be due and payable in full on August 26, 2004.

         2. Prepayments.

         During the first two weeks following each of the first and second
anniversaries of this Note, the Company shall have the right, but not the
obligation, to prepay this Note in part, but not in whole. The maximum amount of
each such prepayment shall not exceed one-third of the original principal
balance of this Note, or $333,333.00, and all interest accrued thereon to the
date of such prepayment. The Company's exercise, or waiver, of its first
opportunity to make a prepayment shall not affect its right to exercise or waive
its second opportunity to make a prepayment; but, in no event, shall any such
prepayment postpone or otherwise delay the payment due upon the expiration of
the term of this Note. In the event that the Company shall choose to prepay this
Note, on either or both such occasions, the Company shall give Holder ten (10)
days prior written notice of its intent to prepay. During such ten-day notice
period, Holder shall have the right, at its option, to convert all or part of
the unpaid principal and accrued interest of this Note into Conversion Shares at
the Conversion Price (as those terms are defined in Section 3, below). Any such
payment shall apply first to the outstanding interest in respect of the amount
of principal so pre-paid, with the remainder of any such payment being applied
as a prepayment of principal.


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         3.       Conversion.

                  (a) Optional Conversion Right. Subject to the terms and
conditions of Section 3(b) hereof, following the first anniversary of this Note
(the "Conversion Period"), the Holder may, at its option, at any time and from
time to time, convert (the "Conversion Right") the unpaid principal balance of
this Note, plus accrued interest thereon, in whole or in part, into shares of
the Company's Common Stock, par value $0.0001 per share (the "Conversion
Shares"), based upon a Conversion Share price (the "Conversion Price") to be
calculated in the manner set forth in the following paragraph and subject to
adjustment as provided in Section 3(d) hereof.

                  For purposes of determining the Conversion Price, the "Fair
Market Value" of one share of the Company's Common Stock shall be calculated in
the manner set forth herein below. If, as of a "Conversion Date" (as that term
in defined in Section 3(b) hereof), the Company's Common Stock is traded on a
national securities exchange or the Nasdaq Stock Market, then the Fair Market
Value of one share of the Company's Common Stock shall be the average of the
closing selling prices thereof, as reported by such exchange or as reported on
the Nasdaq Stock Market for the five trading days immediately preceding the
Conversion Date, or if there were no sales of the Company's Common Stock during
such five-day period, then the Fair Market Value of one share of the Company's
Common Stock shall be deemed to be the closing selling price of the Company's
Common Stock, as reported by such exchange or as reported on the Nasdaq Stock
Market for the next prior trading day on which there were sales of the Company's
Common Stock. If, as of a Conversion Date, the Company's Common Stock is traded
other than on a national securities exchange or the Nasdaq Stock Market, then
the Fair Market Value of one share of the Company's Common Stock shall be the
average of the closing bid and asked prices of one share of the Company's Common
Stock, as quoted on the OTC Bulletin Board or the Pink Sheets, as relevant, for
the five trading days immediately preceding the Conversion Date or, if there is
no bid and asked price during such five-day period, the Fair Market Value of one
share of the Company's Common Stock shall be deemed to be the average of the
closing bid and asked prices of the Company's Common Stock, as quoted on the OTC
Bulletin Board or the Pink Sheets, as relevant, for the next prior trading day
on which there was a bid and asked price. If no such bid and asked price is
available, the Company's Board of Directors shall make a good faith
determination of the Fair Market Value of one share of the Company's Common
Stock using any reasonable method of valuation.

                  The Conversion Price for one Conversion Share shall be the
lesser of (i) 80% of the Fair Market Value of one share of the Company's Common
Stock or (ii) $2.00. Notwithstanding the above, the Conversion Price for one
Conversion Share shall not be less than $1.40. By way of example but not by way
of limitation, if the Conversion Right were to be exercised with respect to
$1,000,000 and if the Conversion Price were $2.00 per Conversion Share, the
Holder would receive 500,000 Conversion Shares ($1,000,000 Conversion Amount
divided by $2.00 Conversion Price/Conversion Share).

                  (b) Mechanics and Condition of Conversion. The Holder may
exercise its conversion rights under Section 3(a) hereof by written notice to
the Company (the "Conversion Notice") stating that the Holder elects to convert
some or all of the principal balance of this Note, and specifying the amount of
such principal balance to be converted (the "Conversion Amount"). In the event
that the Holder elects to convert the remaining principal balance of this Note,
the Holder shall at the time of delivering the Conversion Notice also surrender
this Note. Notwith-


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standing any terms in Section 6(h) hereof in respect of the date on which a
notice shall be deemed to have been delivered, Conversion shall be deemed to be
effective, and the relevant Conversion Price shall be calculated, as of the date
on which the Conversion Notice is received by the Company (the "Conversion
Date") for the Conversion Amount.

                  (c) Issuance of Conversion Shares. As soon as practicable
after conversion of this Note, the Company will, at its expense, cause to be
issued in the name of and delivered to the Holder a certificate or certificates
for the number of Conversion Shares to which the Holder shall be entitled upon
such conversion (bearing such legends as may be required by applicable state and
federal securities laws in the opinion of legal counsel of the Company and as
may be provided for in any applicable contracts between the Holder and the
Company), together with any other securities and property to which the Holder is
entitled upon such conversion under the terms of this Note. All Conversion
Shares issued upon the conversion of this Note shall be validly issued, fully
paid and non-assessable.

                  (d) Fractional Interests. The Company shall not be required to
issue fractional Conversion Shares on the conversion of this Note, in whole or
in part. If any fractions of a Conversion Share would, except for the provision
of this subsection, be issued upon the exercise of the Conversion Right
hereunder, the Company will: (i) if the fraction of a Conversion Share otherwise
issuable is equal to or less than one-half, round down and issue to the Holder
only the largest whole number of Conversion Shares to which the Holder is
otherwise entitled; or (ii) if the fraction of a Conversion Share otherwise
issuable is greater than one-half, round up and issue to the Holder an
additional Conversion Share in addition to the largest whole number of
Conversion Shares to which the Holder is otherwise entitled.

                  (e) Adjustments. The number of Conversion Shares purchasable
upon conversion of this Note and the Conversion Price shall be subject to
adjustment as follows:

                           (i) Stock Dividends, Stock Splits, Etc. In case the
Company shall at any time after the date of this Note (A) declare or pay a
dividend in shares of Common Stock (as hereinafter defined) or make a
distribution in shares of Common Stock, (B) subdivide its outstanding shares of
Common Stock, (C) combine its outstanding shares of Common Stock into a smaller
number of shares of Common Stock or (D) issue any shares of its capital stock in
a reclassification of the Common Stock (including any such reclassification in
connection with a consolidation or merger in which the Company is the continuing
entity), the number of Conversion Shares purchasable upon conversion of this
Note immediately prior thereto shall be adjusted so that the Holder shall be
entitled to receive the kind and number of Conversion Shares or other securities
of the Company which it would have owned or have been entitled to receive after
the happening of any of the events described hereinabove, had the Note been
converted immediately prior to the happening of such event or any record date
with respect thereto.

                           (ii) De Minimus Adjustment. No adjustment in the
number of Conversion Shares purchasable hereunder shall be required unless such
adjustment would result in an increase or decrease of at least one percent (1%)
of the Conversion Price; provided, however, that any adjustments which by reason
of this Section 3(e)(ii) are not required to be made shall be carried forward
and taken into account in any subsequent adjustment.


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                           (iii) Conversion Price Adjustment. Whenever the
number of Conversion Shares purchasable upon the conversion of this Note is
adjusted, as herein provided, the Conversion Price payable upon purchase of each
Conversion Share shall be adjusted by multiplying such Conversion Price
immediately prior to such adjustment by a fraction, of which the numerator shall
be the number of Conversion Shares purchasable upon the conversion of this Note
immediately prior to such adjustment, and of which the denominator shall be the
number of Conversion Shares purchasable immediately thereafter.

                           (iv) Preservation of Purchase Rights Upon Merger,
Consolidation, Etc. In case of any merger, reorganization or consolidation of
the Company into another corporation or entity other than a subsidiary of the
Company (a "Merger"), or in case of any sale of all, or substantially all, of
the assets of the Company or any subsidiary of the Company (a "Sale of Assets"),
the Company shall give ten (10) days written notice to the Holder prior to such
Merger or Sale of Assets. Prior to or contemporaneous with the closing of such
Merger or Sale of Assets, the Company shall, at Holder's election, either (i)
repay all unpaid principal and interest under this Note, (ii) convert this Note
into Conversion Shares at the Conversion Price, or (iii) execute, or cause any
successor or purchasing entity or corporation, as the case may be to execute,
with the Holder an agreement that the Holder shall have the right thereafter to
purchase upon conversion of the Note the kind and amount of Conversion Shares
and other securities and property which it would have owned or have been
entitled to receive after the happening of such Merger or Sale of Assets had
such Note been converted immediately prior to such action. Such agreement shall
provide for adjustments, which shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Section 3(e). The provisions
of this Section 3(e)(iv) shall similarly apply to successive Mergers and Sales
of Assets.

                  (f) Common Stock. For the purpose of this Note, the term
"shares of Common Stock" or "Common Stock" shall mean (i) the class of stock
designated as the Common Stock of the Company at the date of this Note, or (ii)
any other class of stock resulting from successive changes or reclassifications
of such shares consisting solely of changes in par value, or from par value to
no par value, or from no par value to par value. In the event that at any time,
as a result of an adjustment made pursuant to this Section 3, the Holder shall
become entitled to purchase any securities of the Company other than shares of
Common Stock, thereafter the number of such other securities so purchasable upon
conversion of this Note and the Conversion Price of such securities shall be
subject to adjustment from time to time in a manner and on terms as nearly
equivalent as practicable to the provisions with respect to the Conversion
Shares referred to in Section 3(a) hereof.

         4.       Default.

         The entire unpaid principal and accrued interest of this Note shall
become and be immediately due and payable upon written demand of the Holder,
without any other notice (except as may otherwise be set forth hereinbelow) or
demand of any kind or any presentment or protest, if any one of the following
events (each an "Event of Default") shall occur and be continuing at the time of
such demand, whether voluntarily or involuntarily, or, without limitation,
occurring or brought about by operation of law or pursuant to or in compliance
with any judgment, decree or order of any court or any order, rule or regulation
of any governmental body:


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                  (a) If the Company (i) makes a composition or an assignment
for the benefit of creditors or trust mortgage, (ii) applies for, consents to,
acquiesces in, files a petition seeking or admits (by answer, default or
otherwise) the material allegations of a petition filed against it seeking the
appointment of a trustee, receiver or liquidator, in bankruptcy or otherwise, of
itself or of all or a substantial portion of its assets, or a reorganization,
arrangement with creditors or other remedy, relief or adjudication available to
or against a bankrupt, insolvent or debtor under any bankruptcy or insolvency
law or any law affecting the rights of creditors generally, or (iii) admits in
writing its inability to pay its debts generally as they become due;

                  (c) If an order for relief shall have been entered by a
bankruptcy court or if a decree order or judgment shall have been entered
adjudging the Company insolvent, or appointing a receiver, liquidator, custodian
or trustee, in bankruptcy or otherwise, for it or for all or a substantial
portion of its assets, or approving the winding-up or liquidation of its affairs
on the grounds of insolvency or nonpayment of debts, and such order for relief,
decree, order or judgment shall remain undischarged or unstayed for a period of
forty-five (45) days; or if any substantial part of Company Property is
sequestered or attached and shall not be returned to the possession of the
Company or such subsidiary or released from such attachment within forty-five
(45) days; or

                  (d) If the Company is dissolved, liquidated, suspends its
normal business operations or otherwise fails to continue to operate its
business in the ordinary course.

                  (e) If the Company is in breach under the terms of any
agreement with Holder and/or any affiliate of Holder, including this Note, that
has not been cured in accordance with the terms of such agreement.

         5. Corporate Action; No Impairment. The Company will not, by amendment
of its Articles of Incorporation or bylaws, or through reorganization,
consolidation, merger, dissolution, issue or sale of securities, repurchase of
securities, sale of assets or any other action, avoid or seek to avoid the
observance or performance of any of the terms of this Note, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the Holder under this Note against wrongful impairment.

         6.       General

                  (a) Replacement. Upon receipt by the Company of evidence
reasonably satisfactory to it of the loss, theft, destruction or mutilation of
this Note and of indemnity reasonably satisfactory to it, and upon reimbursement
to the Company of all reasonable expenses incidental thereto, and upon surrender
and cancellation of this Note (in case of mutilation) the Company will make and
deliver in lieu of this Note a new Note of like tenor and unpaid principal
amount and dated as of the date to which interest has been paid on the unpaid
principal amount of this Note in lieu of which such new Note is made and
delivered.

                  (b) Designees for Shares. The Holder may designate persons
other than the Holder in whose names the Conversion Shares may be registered and
issued.


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                  (c) Absence of Registration. The Holder acknowledges that none
of the Conversion Shares has been registered under the Securities Act of 1933,
as amended, and agrees the Company shall have the right to require the Holder to
furnish such representations and warranties as to the Holder's investment intent
as are reasonable and customary in the issuance of unregistered stock.

                  (d) Reservation of Shares. The Company represents and warrants
that it has reserved out of the authorized and unissued shares of Common Stock a
number of Conversion Shares sufficient to provide for the exercise of the
Conversion Right provided for by Section 3 hereof. If at any time the number of
authorized but unissued shares of Common Stock or other securities shall not be
sufficient to effect the conversion of this Note, then the Company will take
such corporate action as may, in the opinion of its legal counsel, be necessary
to increase its authorized but unissued shares of Common Stock or other
securities to such number of shares of Common Stock or other securities as shall
be sufficient for such purpose.

                  (e) Successors and Assigns. This Note, and the obligations and
rights of the Company hereunder, shall be binding upon and inure to the benefit
of the Company, the Holder, and their respective successors and assigns.

                  (f) Changes and Indulgences. Changes in or additions to this
Note may be made or compliance with any term, covenant, agreement, condition or
provision set forth herein may be omitted or waived (either generally or in a
particular instance and either retroactively or prospectively), only upon
written consent of the Company and the Holder. Neither the failure nor any delay
on the part of either the Holder or the Company to exercise any right, remedy,
power or privilege under this Note shall operate as a waiver thereof, nor shall
any single or partial exercise of any right, remedy, power or privilege preclude
any other or further exercise of the same or of any other right, remedy, power
or privilege; nor shall any waiver of any right, remedy, power or privilege
constitute a waiver with respect to any other occurrence.

                  (g) Currency. Except as otherwise set forth or expressly
provided for herein, all payments hereunder shall be made in such coin or
currency of the United States of America as at the time of payment shall be
legal tender therein for the payment of public and private debts.

                  (h) Notices. All notices, requests, consents and demands shall
be made in writing and shall be delivered by facsimile to the fax number, if
any, set forth below or by hand, sent via a reputable nationwide overnight
courier service or mailed by first class certified or registered mail, return
receipt requested, postage prepaid;

         If to the Holder:          Nature's Sunshine Products, Inc.
                                    75 East 1700 South
                                    Provo, Utah 84605
                                    Attention:  Daniel Howells
                                    (Fax No.  801-342-4555)

         With a copy to:            Parsons, Behle & Latimer, P.C.
         (which shall not           201 South Main Street, Suite 1800
         constitute notice)         Salt Lake City, Utah 84145-0898
                                    Attention:  Brent Christensen, Esq.


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                                    (Fax Number:  801-536-6111)

         If to the Company:         Cetalon Corporation
                                    1801 Avenue of the Stars, Suite 1830
                                    Century City, California 90067
                                    Attention:  John A. Bryan
                                    (Fax Number:  310-277-0940)

         With a copy to:            Bryan Cave LLP
         (which shall not           2020 Main Street, Suite 600
         constitute notice)         Irvine, California 92614
                                    Attention:  Randolf W. Katz, Esq.
                                    (Fax Number:  949-223-7100)

                  Notices provided in accordance with this Section 6(h) shall be
deemed delivered upon confirmation of facsimile transmission, upon personal
delivery, one business day after being sent via reputable nationwide overnight
courier service, or three business days after deposit in the United States mail.

                  (i) Saturdays, Sundays, or Holidays. If any date that may at
any time be specified in this Note as a date for the making of any payment of
principal or interest under this Note shall fall on Saturday, Sunday, or on a
day which, in Los Angeles, California, shall be a legal holiday, then the date
for the making of that payment shall be the next subsequent day which is not a
Saturday, Sunday, or legal holiday.

                  (j) Governing Law. This Note shall be construed and enforced
in accordance with, and the rights of the parties shall be governed by, the laws
of the State of Utah, notwithstanding any conflict-of-laws doctrines of such
state or other jurisdictions to the contrary, and without the aid of any canon,
custom or rule of law requiring constructions against the draftsman. The parties
agree to submit to the jurisdiction and venue of the state and federal courts of
Salt Lake County, Utah, for the purposes of resolving disputes hereunder and
authorize any such action to be instituted and prosecuted exclusively in the 3rd
District Court, State of Utah, or, if appropriate, the United States District
Court for the District of Utah.

                  (k) Collection Expenses. The Company agrees to pay all costs
of collection or enforcement, including reasonable attorney's fees and legal
expenses incurred by the Holder, in the event that payments are not made under
this Note as required or in the event of the failure of the Company to issue
Conversion Shares as provided for herein.

                  (l) Severability. If any provision of this Note is held
invalid or unenforceable, such invalidity or unenforceability shall not affect
the validity or enforceability of the other provisions of this Note, all of
which are declared severable.

                  (m) Headings. The headings used in this Note are solely for
convenience of reference and shall not affect its interpretation.

                  (o) Words and Phrases. Words and phrases such as "to this
Note," "herein," "hereinafter," "hereto," "hereof," "hereby," "hereinbelow,"
"hereinabove" and "hereunder" when


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used with reference to this Note, refer to this Note as a whole, unless the
context otherwise requires.

                  (o) Gender and Number. Wherever from the context of this Note
it appears appropriate, each term stated in either the singular or the plural
shall include the singular or the plural, and pronouns stated in either the
masculine, feminine or neuter gender, shall include the masculine, feminine and
neuter.

                  (p) Entire Understanding. This Note contains the entire
understanding among the parties hereto with respect to the subject matter
hereof, and supercedes all prior and contemporaneous agreements and
understandings, inducements or conditions, express or implied, oral or written,
except as herein contained. The express terms hereof control and supersede any
course of performance and/or usage of the trade inconsistent with any of the
terms hereof.

         IN WITNESS WHEREOF, the Company has caused this Note to be executed on
its behalf by its duly authorized officer as of the date first above written.

                                             CETALON CORPORATION

                                             By:
                                                 A. John A. Bryan, Jr. President


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