I've read it before, and some of them are really funny, but the guy who makes them is too self-righteous for me.
I just wanna say to him, "It's a webcomic, not your personal soapbox, man. Go complain about how you think people are stupid in your blog or something. Meanwhile, I'll be reading Penny Arcade and laughing my ass off."
I've have too many faves to list out.
comic number 404 is fun :P
anyone read his blog : http://blag.xkcd.com/
i found this article hilarious, now i do this everytime ;) http://blag.xkcd.com/2009/09/02/urinal-protocol-vulnerability/