This is a picture rendered by a raytracer I wrote a few months ago.
It renders spheres, planes & cones/cylinders. Features a nice illumination model,
soft shadow and adaptive supersampling. It has pretty good material handling, you
can have a ambient, diffuse, specular and bump texture on each object.
I've written a very basic tutorial on raytracer and put it on my homepage, http://come.to/polygone
Now I'm off to read Realistic RayTracing by Shirley, a fine book on raytracing.