...appears to be the most-covered song in my music collection: in addition to the 1970 David Bowie original version, I have covers by Lulu (1974), John Cougar Mellencamp (!) (1977), Midge Ure (1982), and the live version by Nirvana (1994).
John Cougar Mellencamp, mind you. Not John Mellencamp, not Johnny Cougar. :-)