I heard a talk a couple of years ago by the Balkan music expert and singer Brenna McCrimmon. She said that what she would do on arriving in a strange town was what every ethnomusicologist would - head for the market and look for the cassette sellers, as they'd have local stuff you'd never find anywhere else.

I liked the way the Kurdish cassette dealers on the Istanbul dockside used to operate - the stock and ghetto blaster was all under a tent-like cover on a very solidly made handcart so they could run like hell with the whole lot if the cops took an interest.

Then you had the guys who sold sectarian songs and flute band music outside Rangers and Celtic matches in Glasgow. You'd expect them to take sides, but instead each one had a barrow with a precisely 50:50 share of red-white-and-blue Protestant stuff and tricoloured Fenian tapes.