When Obi Wan configures the secret transmitter thingy to warn any surviving Jedi to stay the heck away from Coruscant...
Song that is the lure:(Because I can't think of another song that has "come back" in the lyrics right now.)
http://www.youtube.com/watch?v=JYsKDaQIX54
Song that is the warning:
http://www.youtube.com/watch?v=0p7mIvO1uHo
Or just a loop of Monty Python's "run away!"?