When I was at school I helped out on sound and lighting for the school musical, Calamaty Jane. I was sitting in the very back of the hall with my friends and we all had headsets so we could communicate with backstage and there was a teacher on the mic too. We weren't a rich school by any means, so lots of the production had a home-made feel to it, for instance the wagons at the side of the stage were just lunch trolleys with a big cardboard cutout of a wagon on them. It looked good though.
Anyway, it's the end of the play and the entire cast are on stage singing the final song. They're all swaying back and forth and singing their hearts out and at the side of the stage is this girl with bright ginger curly hair. As the ensemble are singing and swaying she passes out, falls off the side of the stage and lands on the wagon trolley which wheels ever so slowly away from the stage. The entire crowd of about 400 parents gasps and stands up to see if she's ok. Aside from the huge gasp the only noise in the hall is me and my friends at the back pissing ourselves with laughter. Next thing I know the head of the production gets on the headset mics and screams at us to shut up, turns out she could hear us laughing from backstage even without the mics. We had to leave the hall we were crying so bad.