Dont Forget the Boys of AC/DC. Or Godley/Creme. But for me, rock aside, the duo to end all duos was Kurt Weill and Bertolt Brecht. What a collection! And they're just fucked-up enough to be real rock and rollers. Oh show me!/The Way!/To the Next/Whiskey Bar!/Ooooh, Don't Ask Why/Ooooh Don't Ask Why/I Tell You We Must Die... jing jin jing jang jan jang, etc...

And that's just the one that made it onto a Doors album. Their whole catalog is aces.