On 11 Jan 1967 Pink Floyd recorded a version of Interstellar Overdrive for inclusion in Peter Whitehead’s film, Tonite Let’s All Make Love In London. Since the band recorded the song in one take, there was some (already paid for) studio time left, so the band recorded a spontaneous jam which was named “Nick’s Boogie.”
This latter track was lost and forgotten until it was rediscovered in the 90s on a reel-to-reel tape covered with mold.