Amanda Palmer, of the Dresden Dolls, performed this majestic version of "Billie Jean" the night Michael Jackson died. I confess to never particularly liking this song, but Amanda's version is sweet and heartbreaking.
And just because one Dresden Doll video isn't enough, my favorite Black Sabbath cover ever (other than the five or so bars the Replacements played one night).
I bring you War Pigs! Turns out piano and drums is just what Ozzy would have ordered, if we wasn't so busy biting the head off bats, or echolocating, or trying to see through his runny mascara, or buying big-ass crosses, or something.