I used to play around with computer graphics as a hobby, and generated some ray-traced animations.

Bounce is a simple GIF animation of a bouncing ball, rendered using POV-ray. The ball's bounce satisfies the laws of physics in that its trajectory follows normal constant downward acceleration and the squish part at the bottom obeys a concocted nonlinear elasticity law. I used this in a physics class to show how animation which doesn't follow the laws of physics (using some other ones) looks bad, because people have a built-in sense of natural physical behavior.

If you like MPEGs, here is a 640x480 MPEG version.

Mate in Five is a five-move checkmate sequence, rendered with POV-ray, an excellent free ray-tracing system. I only animated the moves; the actual chess pieces came from the POV-ray sample file CHESS.POV written by Ville Saari. There are two versions:

matein5.flc, an Autodesk Animator FLC format version. You can view this with an Animator player or XAnim if you are on a Unix machine running X. This is the original format made by putting together all the frames rendered with POV-ray.

matein5.mpg, an MPEG-1 format version. You can view this with VMPEG, mpeg_play and a zillion other MPEG viewers. It's a bit jerky due to the compression; let me know if you have tips on making this MPEG smoother.