I read two webcomics - Hark! A Vagrant and Family Man.
If you like historical/literary humor and don't mind the occasional curse word, check out Hark! Kate Beaton, the author, sends me into fits of giggles very frequently. Don't read it with curious kids in the room.
Family Man is blowing me away. If you aren't scared off by the fact that it's about a Jewish Christian semi-atheist theologian living in eastern Europe circa 1768 and the story is destined to segue into realms of the supernatural, then start reading it here. Her artwork starts out a little rough and the Jewish nose is deliberately exaggerated. But it's fascinating and thought-provoking and the footnotes are wonderful. Oh, and her style has matured with time and her art is becoming absolutely sublime. To wit: