Check out David Gibbons's example, over at geekestateblog.com, of a time lapse video of Elliott bay in Seattle, that he shot with his D70, PowerBook G4, Nikon Capture.
What a great idea! I'm thinking that Canon shooters should be able to do this same thing with Canon's RemoteCapture software. I'm going to try this out with RemoteCapture and my 1Ds this weekend and will report back. Anyone else for a time lapse shot?