Gawker is a really interesting open source app that takes a very
simple, yet powerful, approach to capturing time-lapse videos from an iSight camera - be it your own or someone else's.
As you can see in this image, Gawker can utilize smart networking abilities of Bonjour to see if any other Macs on your
network are running Gawker with an iSight, or you can enable iSight access over the web. You even have control over
image quality, resolution and fps.
Check out the project's examples page for some intriguing samples of what this software can do, such as sped-up footage of snow melting in Colorado and a PowerBook hard drive replacement.
After a little tinkering, I must say Gawker is darn slick and drop-dead-easy to use. But before you ask: I'm not sure if other cameras are compatible. Head over to Gawker's project page for more information.