"Orbit is a satellite simulator. It predicts the motion of satellites using industrial grade orbit propagation algorithms. What you see on this screen is a simulation of over 650 actual unclasiffied satellites with current data from NORAD, earth imagery from NASA, and ploitical boundaries and coastline data courtesy of the United Nations"

I was just watching Steve Job's keynote for WWDC 2004 when I saw this. It's been a while since the last time I was amazed this much. This is a beautifull application.

http://stream.apple.akadns.net/ ( jump to minute 35:30 in the stream )

"Just a few years ago these computations required a defence budget supercomputer. But as you can see the modern G5 just crunches through them."
The author claims he wrote Orbit by himself, in just 3 months, on a powerbook.

There should be a screensaver version comming out somewhere soon. (google couldn't find any info on either the author, the company or the application, though it should be published at apple.com sometimesoon)
... I think I'm going to buy a powerbook just to be able to stare at that screensaver.