SkyRiver is positioning itself as a pure, fully-featured bibliographic utility. SkyRiver subscribers can use bibliographic records from its service without restriction including, presumably, giving them away to non-subscribers. SkyRiver says it is also placing an emphasis on the quality, not quantity, of records. it will launch in January 2010 with 20 million records from the Library of Congress and the British library.
Omeka is a free, flexible, and open source web-publishing platform for the display of library, museum, archives, and scholarly collections and exhibitions. Its five-minute setup makes launching an online archive or exhibition as easy as launching a blog.
‡biblios.net is a web-based original and copy cataloging tool with built in federated search of any Z39.50 target (via an integrated search registry with over 2000 targets - or by adding your own) and a large (30 million strong) shared database of catalog records. This means that you can visit ‡biblios.net and benefit from the work of other catalogers who have gone before you. You can also edit and contribute to the database without any restrictions.
P. Heymann, A. Paepcke, and H. Garcia-Molina. Third ACM International Conference on Web Search and Data Mining (WSDM2010), page 1--10. Stanford University, (February 2010)