The Book of Biff and Maximumble.
Definitely off-beat humor. Unlike some single-panel comics, The Book of Biff actually has the persistence to stick to single-panel comics. *Cough* It also uses a few other unique tricks like having only one character and being entirely pantomime aside from the captions.
Maximumble, done by the same guy, is a bit more mainstream. It's three panels and usually features dialogue, but it's still off-beat and fun in the same way.