the worst I've done is miss a few cues back in high school stuff. Usually songs I wanted nothing to do with (as in I tuned my bass down to dropped C just to keep myself amused). Since then I've only broke strings in front of audiences (actually, my four string is currently sporting the G string that came w/ my five string once more due to thursday night's shenanagins). I've only aborted a song once due to string breakage and that's because we were just barely starting the song. But I'm sure as time goes on I'll find a way to make an ass of myself. I'm pretty good at it after all.