The dizzyingly beautiful screensaver Electric Sheep [1] has been updated to version 2.7b18b, bringing back the multiple display support that was lost in the switch to Snow Leopard compatibility. Other changes include smoother animation, improvements in voting, and various bug fixes to enhance performance and usability. Make sure you download version 2.7b18b, since not all the download links on the site have been updated yet. (Free, 16.6 MB)
[1]: http://community.electricsheep.org/node/50#comment-1488