I have so little free time these days that anything I do for fun has to fit into neat packages of an hour or so (stop sniggering at the back). That's why I LOVE PovRay, the free ray-tracing engine. I only discovered PovRay a little while ago, and within an hour of downloading the software and installing it I produced this little masterpiece:

Povray Robots

Anyone else who has an hour to spare I suggest you do the same!