Following are two screen-savers.

One implements Conway’s game of life, and the other does Recursive Sphere Ray-tracing.

The ray-tracer can be run in ‘application mode’ as well, but it’s pretty nice as a screen-saver.

The spheres are lighted using Phong illumination, including Specular-Highlights, recursion level is limited to your stack, or in other words none

Downloads :

Life Screen-Saver (Source + Win32 Binary) : life_saver.zip
Sphere Tracer (Source + Win32 Binary) : mini_tracer.zip