Shaders doesn’t have to be material on 3D-objects – it can more than that (I’ll come back on how to generate geometries and other stuff in shaders).
I’ve just added an old-school plasma effect (inspired by Omega’s boot sector plasma on the Atari STE) and a Mandelbrot fractal shader. I’m quite impressed by the speed of WebGL, the Mandelbrot uses 100 iterations an is running at 20fps on my Macbook Pro. Please move the mouse to zoom in and out.
To make life easier, there’s a Plane-geometry you can use to set up the attribute streams for vertices and uvs. Note that you have to compensate for the screen’s aspect ratio. Please view the source here and here.