271kochu created a "fountain of cats" in Minecraft by building a structure that extended to the top of the world, then exploiting the game's simple flocking rules for virtual cats to entice the sprites to form a never-ending fountain that is a joy to behold.
Catsplosion (Thanks, Fipi Lele!)
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.