I use vibrate or the standard ring on my iPhone. I always have done the standard one, as stated above, nothing is worse than the way I view someone when their Eminem or Taylor Swift ringtone goes off in a crowded room. I don't know why I do this exactly; it's just an instinctual "REALLY?"
With that said, in Ocean's Thirteen Brad Pitt has a MIDI sounding version of "Don't you want me" by Human League. Also, if you really want to be different, why not do the Sanford & Son theme?