Big signs up all round our folk club calling for silence while people are performing. Once I was in the middle of a number - a pretty difficult number, at that* - when someone's phone rang. And rang. And rang. It was the standard Nokia ringtone, as immortalised by Dom Joly. It turned out to be the MC's phone, which he'd left behind (switched on) while he went to the bar downstairs.

You've got to laugh, really.

*Round Midnight. This was before I got heavily into trad.