There are several MU: 1. Dutch experimental/improvisational underground band from Rotterdam. The band started in 1978 after witnessing a Red Crayola/Scritti Politti performance in cafe "Heavy". The next day they bought instruments and called the band Mentally Unfit taken from Lou Reed's Billy. Soon Backstreet Backlash Records owner Peter Graute would join and the bandname was changed to M.U. or MU so the initials could be used in various projects like The Marijuana Users, More of the Unexpected, Mescal Umbra etc.