Doonesbury: I'm really busy, Zipper.

Today's Doonesbury is the best comic of the day not so much because of the Martin Luther King joke at the end (which is funny), but because of the throw-away gag at the beginning, in which Zonker claims to be busy while sitting around drinking beer and eating potato chips. The joke is, impressively, both specific and universal at the same time, in that it's very much character-based, while nonetheless something everybody does from time to time.