Related Information for Sleepytime Gorilla Museum Sleepytime Gorilla Museum formed in 1999 in Oakland, California, United States. The band was founded by Nils Frykdahl (guitars, flutes, vocals) and Dan Rathbun (bass, log, trombone, lute, vocals) of the band Idiot Flesh, with Carla Kihlstedt (violins, percussion guitar, autoharp, organ, bulbul, vocals) of Tin Hat Trio, 2 Foot Yard and The Book of Knots, after the three worked together in Charming Hostess. Matthias Bossi (drums, glockenspiel, xylophone, vocals) and Michael Mellender (percu.. read more