I thought I'd heard a cell phone go off in just about every situation where it was rude- in restaurants, at the movies, in the bathroom, in class, etc etc- but I was wrong. I heard a DJ's go off in the middle of playing a song on the radio. He didn't answer for a while because it was 80's night and he thought it was part of the synth track. Dumbass.

Cell phone rings have replaced the car alarm as the ill-conceived gadget that everybody thinks is annoying when other people have it, yet they still have it themselves.