Muscle Museum is the second extended play (EP) by English alternative rock band Muse. Limited to 999 hand-numbered copies, was released on 11 January 1999 by Dangerous Records. Four of the EP's five original songs – "Muscle Museum", "Sober", "Uno" and "Unintended" – were re-recorded for the band's full-length debut, Showbiz. The song Instant Messenger was rereleased as a B Side to Muscle Museum under the title Pink Ego Box. This version omits the AOL sample but is otherwise the same recording.