Doug Marlette has a gift for pissing people off.

My favourite has always been Doonsbury. Trenchant, acerbic and an 'equal opportunity offender'.

Phoebe Gloeckner's website has some interesting stuff. (via Susannah Breslin's guestblog on Boingboing).

Update: Also see Best and worst of comics in Times (via LinkMachinego)