Ack... hard to pick just one! For popular music (not including jazz), I think I'll have to agree with you lol_its_fun - David Bowie is quite extraordinary. :)
Though I'd like to add that Mick Jagger, Bryan Ferry, Kate Bush, Paul McCartney, John Lennon, Bob Marley, David Byrne, Donald Fagen, Elton John, and probably some 25+ more are/were pretty good too!
