Sacr3d: A rendering engine toolbox to do 3D graphics in Scheme

It seems it's still early days, but the tutorial has tons of cool examples you can see in your browser. There's a typed s-expression based DSL in Sacr3d that compiles to either Scheme or WebGL shaders, so you can play around with the shader as ordinary Scheme code, or get a visualization in your browser. Dang cool!

(Oh yeah, and it's using Hoot to run in the browser!)