From the GovTrack website:
On this site you'll find the status of legislation, the speeches of representatives on the House and Senate floors, voting records, campaign contribution summaries, and more, plus the opinions of other users through their blog entries. And you can follow only the issues that interest you through email updates and RSS feeds. ... Furthermore, GovTrack cross-references all of its data. That is, speeches on the House and Senate floors are linked to information on the bills mentioned in the proceedings, congressmen are linked to the bills they sponsor, subject keywords are linked to the bills that match those keywords, etc.
via POGO Blog
