Metallica guitarist Kirk Hammett can be seen fishing off the side of Les Claypool's boat in the video for "John The Fisherman"
Les Claypool is one of the few popular players of the Whamola, a type of instrument similar to a gutbucket/washtub bass. The Whamola is played by striking a single string with a drum stick while using a lever to change pitch.
Les Claypool composed and performed the opening songs to both "South Park" and "Robot Chicken"
In the song "Tommy The Cat", singer/actor Tom Waits is the voice of Tommy. Les Claypool plays bass on the Tom Waits album "Mule Variations"