As I mentioned a few days ago on twitter, I took a little time out from regular programming duties to clear my mind. What did I do to relax? Well... I wrote code, of course. :)
Procedurally generated textures and fractals have both interested me for quite some time now. There's a lot of information and inspiration on the web to pull from as well; libraries like libnoise, wikipedia entries on fBm, mandelbrot or voronoi, papers on simplex noise, etc.
Here's a little shot from my work on this. Basically there are 8-10 images, all generated, in a line that you can scroll left and right by moving the mouse. Clicking on an image zooms in.
The whole thing was written modularly as a set of functions that can be snapped together to make more complex patterns. It may become part of Ardor3D in the future if I ever have a chance to clean it all up. :)