Funny you should say that, Spaw. I've just come back from our National Folk Festival, where there are singing sessions in a concrete stairwell every night - quite a small restricted space, and not the most comfortable, but the acoustics are good.

A guy had just sung a couple of short parodies of our favourite sea shanties, introducing them as "Faux Pas" and was just settling down on the step again, when in the silence he did a very audible rumbling FART. Talk about faux pas - you never saw a guy move so fast to get away from us! Dunno how much satisfaction it gave him, but it sure gave us a good laugh - once we felt it was safe to take a breath!