[UPDATE: 01.05.08]
Working on this again... some initial new populations are
here.
The images below were generated from a
single three layer RenderMan shader with approximately 250 control
parameters. These parameters were set by a Perl-based interactive
genetic algorithm. The shader is constructed as two regular grids of
primitive shapes composited over a background. The visual qualities
(e.g. form, position, color, etc.) of the patterns and shapes, as well
as the color of the background, were modified with noise.