Favorite cover songs?

I LOVE the cover of Sweet Dreams! My other favorites include John Mayer's cover of Bold As Love by Jimi Hendrix, and also RHCP's cover of Teenager In Love (originally by Dion and the Belmonts). It sounds a lot different from their usual yet it's awesome! It's on the B-side of By the Way. But I can't forget to include Regina SPektor's cover of No Surprises, by Radiohead. It's beautiful!