Bruce Conner -- avant-garde cinematic giant, co-founder of one of the first and most important film distribution co-operatives, and spiritual godfather to all youtube mashup artists (though most of them are clueless to the fact) -- is dead at the age of 74. GreenCine is compiling links to obituaries and remembrances. Valse Triste, a haunting film that draws on his midwestern childhood, is the film of his that most feels appropriate to watch today. You can find it on YouTube, but its quiet power is utterly diminished by the small screen.
So instead I offer this, the first film of his that I saw, which turned me onto his work: Mongoloid