Agnés Varda: Mur Murs (1980), a documentary on street art and culture in Los Angeles circa 1980.I remember seeing this guy's work in a Bicycle Motocross Action magazine ad when I was a kid and thinking it was cool... I'll see if I can dig it up.

Anyway... embedding is disabled but you can watch Mur Murs in six parts on YouTube.

(hat-tip egotripland)

...

UPDATE: Here's that ad from the BMX magazine: