I'm really sorry if this has been diaried already, but trying to search on Washington Post brings back a LOT of entries.... Anyway, washingtonpost.com has created an interesting tool for checking on and keeping up with votes by U.S. Senators and House Reps, the
Congress votes database. It lets you "browse every vote in the U.S. Congress since 1991" by session, by member and more.
You can subscribe to an RSS feed of votes by your reps. You can compare your reps' votes to the official positions of Democrats and Republicans.
(One of the first things I did there was check on Lieberman :). He did actually vote with the Democrats on some issues lately... ) You can look at votes in specific categories such as "late night votes" or bills with "narrow" and "wide" margins.
All this is public information already, of course, but this database makes that information easily accessible in some new ways and offers potential hours of amusement for political junkies. I'm not connected with the Post in any way, although I have met the tech guy responsible for this project a couple of times, an extremely talented Web developer named Adrian Holovaty who also created the chicagocrime.org site in his spare time.