Metallica

Originally released in 2000, on the soundtrack to the film Mission: Impossible II, "I Disappear" finds Metallica incorporating faintly grungey choruses into a shiny reworking of the "Enter Sandman" riff. It may have confounded some fans at its initial appearance, but if anything, the song proves Metallica was (and is) a band unafraid to change their approach. This came out on the heels of Load, their now-infamous country record so the diehards were understandably confused. Still the riff is mega and those choruses, while melodic, are catchy as hell.