This article is substantially over my head, but I thought it might be interesting to those writing shaders or pro users who have access to OpenGL.
Actually, the article just covers the basics of setting up a simple image processing pipeline. Most of that (temporary buffers, effects chaining) is handled by Unity - to write image effects you just have to produce something in the destination render texture given the source texture.
Oh, and the scripting documentation in 1.5.1 even has some examples 
Brilliant! And an excuse for me to muscle up and learn learn some OpenGL code, gosh dang it!