MOTIENT CORP
OCTOBER 12, 2001 LETTER AGREEMENT
<DOCUMENT>
<TYPE>EX-10.54C
<SEQUENCE>7
<FILENAME>ex1054c.txt
<DESCRIPTION>OCTOBER 12, 2001 LETTER AGREEMENT
<TEXT>
                                 EXHIBIT 10.54c

                               Motient Corporation
                              10802 Parkridge Blvd.
                           Reston, Virginia 20191-5416



                                                              October 12, 2001





Rare Medium Group, Inc.
28 West 23rd Street
New York, New York 10010
Attention:  General Counsel

                           RE:      Note Purchase Agreement

Ladies and Gentlemen:

     Reference is hereby made to the Note  Purchase  Agreement  between  Motient
Corporation (the "Company") and Rare Medium Group, Inc. (the "Purchaser"), dated
as of April 2, 2001, as amended by letter agreements,  dated October 1, 2001 and
October 8, 2001,  pursuant to which the  Maturity  Date was extended as provided
therein (as so amended,  the "Note Purchase  Agreement").  All capitalized terms
used but not otherwise  defined  herein shall have the meanings set forth in the
Note Purchase Agreement.

     The  Purchaser  and the Company  hereby agree that (a)  effective  upon the
Purchaser's  acceptance of this agreement by signing this agreement in the space
provided  below,  the  Company is  repaying  its  obligations  in respect of (i)
$14,058,055.56  of the  principal  of the  Tranche A Note and  $1,631,944.44  of
accrued  interest on the Tranche A Note through the delivery to the Purchaser of
three  million  (3,000,000)  XM  Shares  in  accordance  with the Note  Purchase
Agreement  and (ii)  $9,704,791.67  of the  principal  of the Tranche B Note and
$755,208.33  of accrued  interest on the Tranche B Note  through the delivery to
the  Company  of two  million  (2,000,000)  XM  Shares  in  accordance  with the
provisions of the Note Purchase  Agreement and (b) effective with the repayments
referred  to above,  the  Maturity  Date for the  $10,941,944.44  balance of the
principal of the Tranche A Note (and interest that accrues  thereon) and for the
$15,295,208.33 balance of the principal of the Tranche B Note (and interest that
accrues  thereon) is being  extended to the earlier of (1) 60 days from the date
hereof and (2) the date on which the Company or any of its subsidiaries sells or
otherwise transfers after the date hereof any of its interest in MSV (as defined
below) or sells or  otherwise  transfers  after the date hereof in excess of one
million  (1,000,000) XM Shares  (cumulatively in one or more  transactions),  it
being  understood  that the  transfer of  5,000,000  XM Shares to the  Purchaser
pursuant to this  agreement  shall not be deemed a sale or transfer for purposes
of clause (2) (the earlier to occur of (1) or (2) being hereinafter  referred to
as the "Trigger Date").  Simultaneously with the delivery of this agreement, the
Company is  delivering to the  Purchaser  and XM the letter  attached  hereto as
Annex A directing the  conversion  and  reissuance of the 5,000,000 XM Shares in
the  name  of the  Purchaser  and  otherwise  causing  simultaneously  with  the
repayment a  certificate  representing  the  appropriate  number of shares to be
issued  in the name of,  and  delivered  to,  the  Purchaser.  In  addition,  in
consideration  for the extension of the Maturity Date being granted hereby,  the
Company  shall  use its best  efforts  to  obtain  all  necessary  consents  and
approvals to allow the Company to grant to the Purchaser a security  interest in
the  assets  securing  the  Company's   obligations  to  its  bank  lenders  and
guarantors,  including, without limitation, the Company's ownership interests in
XM, Motient  Holdings,  Inc. and Mobile Satellite  Ventures LLC or any successor
thereto (Mobile Satellite Ventures LLC and such successors collectively, "MSV").
Such  security  interest  shall be junior in priority to the  existing  security
interests of the Company's  bank lenders and  guarantors and senior to any other
lenders or creditors of the Company.  The terms of such security  interest shall
be  substantially  similar  to the  agreements  pursuant  to which the  security
interests were granted to the Company's bank lenders and guarantors, except that
the terms  defining  the  Purchaser's  rights  while  the  holder of a junior in
priority security interest as described above shall be on terms  satisfactory to
the  Purchaser.  In the event such  consents and  approvals  are  obtained,  the
security  interests  contemplated  by the  immediately  preceding  sentence  are
granted  and  the  Purchaser  receives  appropriate  certificates  and  opinions
confirming  the  foregoing on or prior to the Trigger  Date,  the Maturity  Date
shall be  extended  to the date  which is 365  days  from the date  hereof.  The
extension  of  the  Maturity  Date  contemplated  by the  immediately  preceding
sentence  shall be  effective  immediately  following  the  satisfaction  of the
conditions referred to therein. Thereafter, upon the request of the Company, the
Purchaser  shall confirm such  extension in writing.  The Company's  obligations
under the Note Purchase  Agreement shall otherwise  remain in effect as provided
therein,  except to the extent  provided  below with  respect to the transfer of
registration rights.

     In  addition,  the Company  hereby  transfers to the  Purchaser  one of its
"Demand  Registration"  rights  under  Section  2.1(f)  of the  XM  Registration
Agreement  and all  rights  associated  with  such  Demand  Registration  right,
including  those rights set forth in the last two sentences of Section 2.1(f) of
the XM  Registration  Agreement.  Such Demand  Registration  right shall also be
subject  to the  limitations  set forth in the XM  Registration  Agreement.  The
Company  agrees to promptly  notify XM that such  transfer has occurred and upon
request of the  Purchaser  the Company will execute such further  documents  and
instruments  reasonably  necessary  to vest such  rights in the  Purchaser.  The
Company  represents  and  warrants  to the  Purchaser  that the  Company has not
transferred   to  any  other   transferee  the  right  to  initiate  any  Demand
Registration (as defined in the XM Registration Agreement). The Purchaser agrees
that it will not exercise the Demand Registration right transferred  pursuant to
this agreement  prior to December 31, 2001 without prior written  consent of the
Company.

     The parties  acknowledge and agree that the Purchaser's new mailing address
for  notices  shall be as set  forth  above  and its new  number  for  facsimile
transmissions shall be (646) 638-9716.

     This  agreement may be executed and delivered in two or more  counterparts,
and by the different Parties hereto in separate counterparts, each of which when
executed and delivered  shall be deemed to be an original but all of which taken
together shall constitute one and the same agreement.

     This agreement shall be governed by, and construed in accordance  with, the
laws of the State of Delaware  without  regard to any principles of conflicts of
law.

     Please  acknowledge your  understanding of and agreement with the foregoing
by signing this agreement in the space provided below.


                                           Sincerely,

                                           MOTIENT CORPORATION



                                           By:/s/Walter V. Purnell, Jr.
                                           ----------------------------
                                           Name: Walter V. Purnell, Jr.
                                           Title:   President and
                                                    Chief Executive Officer



AGREED TO AND ACCEPTED
This 12th day of October, 2001

RARE MEDIUM GROUP, INC.


By:/s/Glenn Meyers
------------------
Name: Glenn Meyers
Title:   Chairman and
         Chief Executive Officer


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</DOCUMENT>
