OpenGL Demos

I've written an implementation of Preetham's "A Practical Analytic Model for Daylight", an ambient occlusion demo, a vertex buffer object demo, and a GLSL per-pixel lighting demo, I'll post them soon. Tomorrow I'm going to start on a reflection/refraction demo. I'll likely follow them up with a set of tutorials explaining them in some detail; I'd like to start doing more tutorials.