EXHIBIT 10.66

           AGREEMENT TO PURCHASE AND SELL PARTIAL INTEREST IN AIRCRAFT

THIS AGREEMENT TO PURCHASE AND SELL PARTIAL INTEREST IN AIRCRAFT (the
"AGREEMENT") is made and entered into as of this 27th day of September, 2004, by
and between Nelnet Corporate Services, Inc., f/k/a Nelnet Corporation (herein
referred to as "Seller"), and Crete Carrier Corporation ("Crete Carrier") and
Nebco Intermodal, Inc. ("Nebco"), (Crete Carrier and Nebco being referred to
herein individually as a "Purchaser" and collectively as the "Purchasers"), with
respect to That certain Cessna Citation Excel model aircraft, Serial No.
560-5270, Reg No. N300DA (the "Aircraft")

NOW, THEREFORE, in consideration of the mutual covenants hereafter contained,
the parties hereto agree as follows:

1.      Sale of Seller's Interest in Aircraft. Seller hereby agrees to sell,
        assign, transfer and deliver to Purchasers and Purchasers hereby
        severally agree to purchase from the Seller, under and pursuant to the
        terms and conditions hereafter set forth, Seller's undivided aggregate
        45% ownership interest in the above referenced Aircraft in the following
        proportion: (i) an undivided 30% interest in the Aircraft shall be
        transferred to Crete Carrier, and (ii) an undivided 15% in the Aircraft
        shall be transferred to Nebco.

2.      Purchase Price. The purchase price for the portion of Seller's ownership
        interest in the Aircraft purchased by Crete Carrier shall be Two
        Million, Three Hundred Eighty Two Thousand, One Hundred Seventeen
        Dollars ($2,382,117.00). The purchase price for the portion of Seller's
        ownership interest in the Aircraft purchase by Nebco shall be One
        Million, One Hundred Ninety One Thousand, Fifty Eight Dollars
        ($1,191,058.00).

3.      No Encumbrance. The Seller's interest in the Aircraft shall be
        transferred to Purchasers free and clear of all security interests,
        liens or encumbrances of any nature whatsoever.

4.      Closing. The Closing shall be set to occur no later than 2 business days
        after execution of this AGREEMENT. Closing shall take place as evidenced
        by executing and filing an FAA Aircraft Bill of Sale (AC Form 8050-2)
        with the FAA Aircraft Registry on behalf of Purchaser, and wire
        transfering the Purchase Price to Seller or its designated Qualified
        Intermediary, per their written instructions, and by delivery to the
        respective Purchasers of a Bill of Sale in the form attached hereto as
        Exhibit A.

5.      Risk of Loss. Risk of loss, damage, or destruction of the Seller's
        interest in the Aircraft shall pass from Seller to Purchasers upon
        Closing of the sale of Seller's interest in the Aircraft.

6.      Representations. Seller represents and warrants that it is the sole
        owner of an undivided 45% interest in the Aircraft, that it has good and
        merchantable title to an undivided 45% interst in the Aircraft, and that
        Seller's interest in the Aircraft will be transferred to the respective
        Purchasers free and clear of all security interests, liens, claims, and
        encumbrances whatsoever. Seller further represents and warrants that it
        has no knowledge of any defect or deficiency with respect to the
        Aircraft.

        EXCEPT FOR THE WARRANTY OF TITLE EXPRESSLY SET FORTH HEREIN, "SELLER"
        MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND OR NATURE REGARDING
        THE "AIRCRAFT", WHICH ARE DELIVERED HEREUNDER IN AN "AS IS, WHERE IS"
        CONDITION. WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, "SELLER"
        DISCLAIMS ALL OTHER WARRANTIES, GUARANTEES OR LIABILITIES, WHETHER
        EXPRESS OR IMPLIED OR STATUTORY, SUCH AS THE CONDITION OF THE "AIRCRAFT"
        AIRWORTHINESS, DESIGN, QUALITY OF WORKMANSHIP OR MATERIALS,
        MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


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7.      BROKER'S COMMISSION. Seller and Purchasers each represent and warrant to
        the other that they have taken no action which would obligate the other
        parties or give rise to a valid claim for a broker's fee in connection
        with this transaction and each party agrees to indemnify and forever
        hold the other harmless from and against any claims for brokers'
        compensations, fees, or commissions arising out of the indemnifying
        party's actions.

8.      TAXES. Purchasers shall pay, and shall indemnify and hold the Seller
        harmless from all sales, use, property, ad valorem, value added, or
        other similar taxes, fees, or other charges of any nature (excluding
        taxes on net or gross income or gain realized by the Seller) together
        with any penalties, fines, or interest thereon which may be assessed or
        levied by the U.S. Government or other U.S. taxing authority as a result
        of the Purchasers' acquiring Seller's interest in the Aircraft. Seller
        shall be responsible for any taxes, fees, or charges assessed against
        the Aircraft prior to Closing and shall indemnify and hold Purchasers
        harmless from these taxes.

9.      PRIOR AGREEMENTS. This AGREEMENT sets forth the entire contract between
        the parties and supersedes all previous communications, representations,
        or agreements, whether oral or written, between the parties with respect
        to the sale and purchase of Seller's interest in the Aircraft. The
        parties agree that the Aircraft Joint Ownership Agreement dated as of
        August 22, 2002 (the "Ownership Agreement") between Seller and
        Purchasers is hereby amended to delete Seller as a party thereto, and to
        transfer Seller's rights and obligations pursuant to the Ownership
        Agreement to Purchasers in the same proportion as Seller's ownership
        interest in the Aircraft is being transferred (30% to Crete Carrier and
        15% to Nebco). The Purchasers further acknowledge that Seller has fully
        satisfied its obligations under the Ownership Agreement and the Seller
        shall have no further duties or obligations in connection with the
        Ownership Agreement. Purchasers shall severally assume all of Seller's
        obligations under the Ownership Agreement arising after the Closing of
        the sale pursuant to this AGREEMENT in the same proportion as Seller's
        ownership interest in the Aircraft is being transferred hereunder.
        Purchasers shall use best efforts in good faith to terminate or amend
        the Aircraft Management Agreement dated as of August 22, 2002 (the
        "Management Agreement") between Duncan Aviation, Inc. ("Duncan"),
        Purchasers and Seller, so as to remove Seller as a party to such
        Management Agreement, and that Purchasers hereby severally assume all of
        Seller's obligations under the Management Agreement arising after the
        Closing of the sale pursuant to this AGREEMENT in the same proportion as
        Seller's ownership interest in the Aircraft is being transferred
        hereunder . Purchasers agrees to indemnify and hold harmless Seller for
        any claim of Duncan under the Management Agreement arising on or after
        the date of Closing.

10.     AMENDMENTS. This AGREEMENT may be amended only by a written instrument
        executed by all parties.

11.     AUTHORIZATION. Seller and Purchaser each warrant to the other that the
        execution, delivery, and performance of this AGREEMENT has been
        authorized and approved by all required corporate action, and the
        parties executing this document warrant their authority to so bind the
        respective parties.

12.     COUNTERPARTS. This AGREEMENT may be executed in two or more
        counterparts, each of which shall be deemed an original and shall be
        effective when executed by both parties.

13.     GOVERNING LAW. This contract shall be deemed to have been made, executed
        under and governed by the law of the State of Nebraska.

                                       2
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14.     1031 EXCHANGE. Seller and/or Purchasers may structure the transaction
        herein contemplated as the receipt of replacement property pursuant to a
        like-kind exchange under the provisions of Section 1031 of the Internal
        Revenue Code of 1986, as amended, and the Treasury Regulations
        promulgated thereunder (the "Regulations"). It is expressly acknowledged
        that Seller and/or Purchasers may assign its rights in this AGREEMENT to
        a qualified intermediary as defined in the Regulations ("Qualified
        Intermediary") and at Closing, at the request of Purchasers or the
        Qualified Intermediary, Seller will transfer title to the Aircraft to
        Purchasers, the Qualified Intermediary or to an "Exchange Accommodation
        Titleholder" as defined in Revenue Procedure 2000-37, 2000-2 C.B. 38.
        Any assignment of this AGREEMENT shall be in writing and notification of
        the assignment shall be given to Seller and/or Purchasers in writing at
        or before Closing. Seller and/or Purchasers will cooperate with Seller
        and/or Purchasers if requested by Seller and/or Purchasers to structure
        the transaction in such manner, and will execute any documents that
        Seller and/or Purchasers may be reasonably requested to sign that are
        consistent with this AGREEMENT, provided Seller and/or Purchasers incur
        no additional cost or expense and are held harmless against any
        liability arising because of the intended like-kind exchange or any
        challenge to or failure of this transaction to qualify for such
        treatment. The conclusion of such like-kind exchange shall not be a
        condition precedent to the conclusion of this AGREEMENT, or payment for
        the Seller's interest in the Aircraft.


  IN WITNESS WHEREOF, the parties hereto have executed this AGREEMENT TO
  PURCHASE AND SELL PARTIAL INTEREST IN AIRCRAFT by their duly authorized
  representative, the day and year first above written.


Nelnet Corporate Servcies, Inc., f/k/a            Crete Carrier Corporation
Nelnet Corporation



By:  /s/ Terry J. Heimes__                         By:    /s/ Tonn M. Ostergard
     ---------------------                                ---------------------

     Chief Financial Officer                              President
     -----------------------                              ------------------
     Name and Title                                       Name and Title


Nebco Intermodal, Inc.


By:   /s/ Stan Malz
   --------------------------

   --------------------------
   Name and Title



<PAGE>


                                   EXHIBIT A.



                              WARRANTY BILL OF SALE



        KNOW ALL MEN BY THESE PRESENTS:

That Nelnet Corporate Services, Inc., f/k/a Nelnet Corporation ("SELLER"), in
consideration of the sum of ONE DOLLAR ($1.00) and other good and valuable
consideration paid to it by Crete Carrier Corporation and Nebco Intermodal, Inc.
(collectively, the "Purchaser"), the receipt of which is hereby acknowledged,
hereby sells, grants, transfers and delivers to Purchaser, its successors and
assigns all of SELLER's undivided 45% right, title and interest in and to the
airframe described as Cessna Citation Excel Serial Number 560-5270, together
with the engines installed thereon, together also with all equipment,
components, appliances, parts, instruments, avionics, appurtenances,
accessories, furnishings and other equipment of whatever nature installed in or
attached to the airframe or the engines ("Components"), together also with all
loose equipment and documents in the airframe and spare parts associated with
the airframe, engines or components, together with all repair or maintenance
agreements or programs relating to the airframe, engines or components, all
pursuant to that Agreement to Purchase and Sell Partial Interest in Aircraft
dated as of September ___, 2004 (collectively, the "Aircraft").

        That SELLER hereby warrants to PURCHASER, its successors and assigns
that it is the holder of title to an undivided 45% interest in the Aircraft and
has the right to sell the same as aforesaid and that this Bill of Sale conveys
to PURCHASER good and marketable title to an undivided 45% interest in the
Aircraft, free and clear of all security interests, liens, claims, charges and
encumbrances of any nature whatsoever, and that SELLER will warrant and defend
such an undivided 45% interst in title forever against all claims and demands
whatsoever.

        That SELLER agrees and acknowledges that the terms and conditions of
this Bill of Sale shall survive the delivery of this Bill of Sale and the
recording of this or any Federal Aviation Administration Bill of Sale.

        IN WITNESS WHEREOF, SELLER has caused this Bill of Sale to be signed by
its duly authorized officer this ________ day of ______________________, 2004.



                                    Nelnet Corporate Services, Inc.,
                                    f/k/a Nelnet Corporation


                                    By:____________________________

                                    Its:____________________________