Dug out my old iterated function system generator to make a new logo for the site. Some of the other results are in this gallery:
http://arklyffe.com/gallery/v/cg/chargetraces/

These are simply images of a large number of particle trajectories in a "lumpy" force landscape. In a simple example:
http://arklyffe.com/gallery/v/cg/chargetraces/spark.jpg.html