If you do this collaborate soundtrack project again, I'd love to participate!
In the 1990s I saw a double-bill (projected on film) of Man with a Movie Camera and The Crowd.
It screened at the Castro Theater in San Francisco and the soundtrack was performed live by the Alloy Orchestra.
It was a fantastic pairing of films because it showed two perspectives on the crowd/the masses. The Crowd,
directed by King Vidor, is an absolutely amazing film about capitalist workers in a busy metropolis trying to
find meaning through purchasing entertainment and finding love at Coney Island during their "free time". It has
lots of shots of the geometrical/impersonal machinery of capitalist working environments whereas
Man with a Movie Camera is more lyrical and utopian in its celebration of how people can fit into the
kaleidoscopic machinery of human society in order to craft a egalitarian Marxist society together.
The King Vidor film, on the other hand, presents the idea that individuals must hold onto their individuality in the face
of the the impersonal meat-grinder of capitalism which churns individuals into a pink paste of "the crowd".
Here is a pic from The Crowd.

Also:
[youtube]http://www.youtube.com/watch?v=Er7kOfPGbmQ[/youtube]