Bloom County was one of my favorite comic strips while it was still running. Although it's a little off-putting at first glance to see just how much text is involved, Berkeley Breathed's adept turns of phrase, his insightful sense of humor and willingness to mock his own medium made it one of the best strips I've ever read. And of course it doesn't hurt that one of its main characters is a sweet penguin named Opus. :)
Tunes for our Times
Bloom County Babylon
Billy and the Boingers Bootleg
Penguin Dreams and Stranger Things
Goodnight Opus
Politically, Fashionably, and Aerodynamically Incorrect