On the train home last night, there was a young metally-looking dude listening to his iPod and with his eyes closed, he was playing air-drums along with what he was listening to... doing fills and all sorts of crazy patterns... and he was enjoying himself immensely, harming no-one. Some people in the carriage were looking at him like he was demented, I couldn't keep a smile off my face while being slightly embarrassed. I've also been known to have a little boogie in the supermarket, before catching myself and behaving like a grown-up. What, in your view, is permissable in public? A little bit of head-nodding or pretending you're in an iTunes commercial?