24 is amazingly addicting, others include but are not limited to (in no particular order):
Family Guy
Smallville
Sopranos
The OC 🙂D I know, don't say it)
SG-1 (most seasons)
CSI
South Park
MTV shi* (real world, road rules, battle of the sexes) (mostly poor programs but addicting for background noise)
Battlestar Galactica
Alias
More I am sure, this suffices. To actually answer the question, favorite is probably 24 but it could influenced because I just finished season 4 HD rips of Fox 🙄, thankfully French co-workers like it too and aquired it for me.
Far too many I'll admit, but being in college and unmotivated to study, I watch a lot of television. Funny thing is being France with no TV, other than the shows I left mid-season, I don't feel like I am missing anything, which I'm glad I can say otherwise I would be worried.