Covers: Everything Old is New Again (And Awesome!)

So I've got a thing for covers. Love 'em.  Something about being like "Wait-- I know this song... don't I?"   To me, the best covers stay true to what made the song great in the first place, but add in something new and unexpected from the the covering artist. 

Mat Weddle's cover of Outkast's "Hey Ya"  does just that, I think. Some of my other faves: William Fitsimmon's cover of Kanye's "Heartless" and Jay Brannan's cover of The Verve Pipe's "Freshman".

What about you? Got a favorite cover?