Platform: Windows XP, Windows Vista
Number of downloads: 8541
Electric Sheep uses your PC's idle power to generate intense fractal animations which are then displayed as a screensaver.
It works a little bit like distributed computing, as the software communicates with all other installed copies of Electric Sheep over the internet.
Once in communication the work of creating the fractals is shared by all, so the results can be pretty impressive and better than you'd get from the power of one PC.
The developer of the screensaver calls the fractal animations "sheep", and users can vote for their favourite animations simply by pressing keys on the keyboard while the animation is playing.
The popular sheep survive longer than the rest, and they can even reproduce based on an algorithm that allows for mutation.
You'll need a fairly powerful PC and an always on, high-bandwidth internet connection. Any generated fractals will take time, and you'll need to run the software for a few hours initially to make contact with enough fellow users.