Come and Get It, Performed by Badfinger
This classic Badfinger song was, as all fans know, written and produced by Paul McCartney. He made sure that the singer sounded as much like him as possible. One wonders why he didn't just sing it himself - but the song wound up making Badfinger's career. Since I posted Paul's demo version, I figured I might as well post the finished Badfinger product.
Paul's slightly slower demo version is here. Note how uncanny is the resemblance between the voices of Paul and Badfinger's lead singer.