I remember at the Edinburgh Festival one time, I was playing away while, among others, a large American fella (with wide, loud checked trousrs) was filming me on a hand-held but making not the slightest signs of actually throwing any dosh. Another (seasoned) Busker went by, and saw the situation at a glance, and said, "C'moan, gie's yer camera and I'll fillum ye pittin' in a coin..."