1) Simpson's -- it's just classic and quite funny the way they poke fun at society and the norm.
2) Futurama -- I get to watch it so rarely, but the lines are so great in it. My current fav: "I've never seen a supernova explosion, but if it's anything like my Chevy Nova this is going to one great show!"
3) Family Guy -- good show, funny, but again, I don't get to see it much.