Pink Floyd: 25 Million Gloomy Punters Can't Be Wrong

Right now, someone, somewhere on this planet is playing Dark Side Of The Moon. Released 20 years ago this month, its mixture of blues and electronics, passion and misery, has struck a doomy chord with at least two generations of fans and musicians and made it one of the best-selling British albums of all time. Stuart Maconie unravels this mysterious record's birth pangs and abiding influence.