How to develop 3d procedural textures?

Can somebody tell where I can find guides or tutorials or explanations about programing procedural textures? Better if 3d, 3d procedural textures. I can’t find appropriate resources. If I search, I find how to map procedural textures and things like this. I would like to try some new ideas.

There’s a big thread on here about pynodes that has a bunch of examples to get you started – unfortunately pynodes didn’t make the jump from 2.4->2.5 so you’ll be stuck with 2.49 if you want to play with them.

Also, you know, google’s good for finding random stuff…