It never fails to amaze me how powerful raytracing is. Last year I took an "Image Synthesis" class and did a quick presentation about a post I've seen here on HN about a raytracker in 1337 bytes [0]. It is amazing how such a small program can generate an image with depth of view, shadows and texture.

0: http://fabiensanglard.net/rayTracing_back_of_business_card/i...