Stefan sez,
The Prelinger Archives is an incredible collection of old films, many of them accessible via its website.
In addition to old industrial films, quaint hygiene lessons for teenagers, and jaw-dropping things like footage of pre-1906 quake San Francisco, the site now features contributed mashups.
I particularly like "Planet Earth: Our Response," a dreamy mix of archive footage (assembled to look like an introduction to Earth culture) and shots of a guy mucking around with an alien probe.
