The Daily Show when I happen to catch it.

Regularly:
ER
Friends (well, not anymore obviously, but for the entire run of the show)
Third Watch
West Wing
Six Feet Under
The Sopranos
Queer as Folk
The L Word

[Edit: I forgot to add ...]
Irregularly:
Reno 911 (funny!)
Animal Cops
Law and Order (whichever)
various animal shows
documentaries (all kinds of subjects)