MAPLight.org
MAPLight.org is a public database that provides information on campaign donations and their connection to legislative votes. MAPLight’s purpose is to make the legislative process more transparent.
The MAPLight.org site includes a list of current bills in Congress, information on legislators and the top 10 interests groups donating to each legislator, and public discussion forums.
There is a positive review of this site in the July, 2009, issue of Library Journal online.