Local codesmith Andrew (née Android) Stone http://stone.com turned me on to Electric Sheep, an open source project he's working on. Per the electricsheep.org http://electricsheep.org guided tour, here is the deal: “The proliferation of powerful computers with high-bandwidth network connections forms the substrate of an expanding universe. The electric sheep and we their shepherds are colonizing this new frontier.” Yep, the Matrix again, except this time in reverse: the sheep (as each screen saver permutation is termed) evolve, reproduce and mutate based on the aggregate whims of users Internetwide, voting up or down. Like SETI@home, it's a distributed computing environment: Each installation communicates with all other installations, building a consensus reality for electronic creatures. So much cooler than MySpace.
Electric Sheep adapts to many environments, a useful evolutionary trait: Windows, Mac OS X, Linux and FreeBSD. One caveat: the initial sheep download can take all night. They are dreams, after all.