A good thing: the Washington Post’s Congress Vote Database.
It’s a database of all votes cast in the U.S. parliament. You can see who voted for and against which laws and even get RSS feeds for the votes of individual politicians.
Transparency is good, and this seems to be a good way to keep tabs on the actions of your elected representative.
Any fellow Germans know about similar projects (or possible sources of data for this) for our country? I think this would be much harder here because votes in the Bundestag are not recorded individually. Politicians just raise their hands or stand up and a tally is taken.
[Update: Added missing link.]