I myself use Kurt Cobain's mutated power chords using only the index and ring finger rather then the standard three finger set up.
for reggae I confuse the hell out of people by insisting on using the Bob Marley chords by playing the major and minor chords with the index and middle fingers on the higher strings rather then barring down with the pad of the index finger standard style.
and lastly, though I have not the dexterity to use my thumb, I also have Hendrix's habit of using the pinky finger to play power chords cobain style rather then standard.
these are my bastardized guitar playing styles which tend to confuse people who are more purists when you are playing together and they are watching your hands to find their place...
what do y'all players do that is far from standard?