Whose Line is it Anyways was really good, but the re-runs just don't have the same awesomeness that they did when they were new.
Funniest shows are South Park and Seinfeld (even if you've seen every episode a million times they are still funny)
I bet I've got some good ones not many people would know.
Corner Gas - the style of comedy is basically like Seinfeld, except its based in a small town in Saskatchewan
Tim and Eric Awesome Show Great Job! - Absolutely Hilarious, basically a random skit comedy show
1. The Office (you can never get enough)
I've never found The Office funny. The Original, or the American...Steve Carrell has never done anything for me, and the only thing I like Ricky Gervais in is Extras.
Dexter has some of the best dry humor on tv in my opinion. It's not a belt out laughing humor, but just something that continuously lightens the mood after seeing kill after kill.