I recently came across this small application called pixel-lapse. The basic principle sounds interesting: record a webcam image one pixel at a time. From the photo gallery on the web site, it looks like you get the most interesting results when part of the image is static and part of it moves. So I decided to give it a go and here's the first shot:
Interesting result indeed! Shame about the watermark though. I'd happily pay a few quid for a version without the watermark but it doesn't seem to be an option on the web site.