From a partnership between the National Endowment of the Humanities and the Library of Congress comes the National Digital Newspaper Program (NDNP).
Over a period of approximately 20 years, NDNP will create a national, digital resource of historically significant newspapers from all the states and U.S. territories published between 1836 and 1922. This searchable database will be permanently maintained at the Library of Congress (LC) and be freely accessible via the Internet.
Phase one of the project is expected to be launched September 2006.
Thanks to my colleague, Mary Jo Koranda, for the tip.