I'd just like to show some of the source material for my project for the Punto y Raya festival. All video so far has been created entirely with Processing, with heavy use of toxiclibs. Basically, various lines are generated with move across the screen at different rates and the intersections between the lines are colored with dots. From there, various combinations of filters (blur, erode, dilate, etc.) are used to create the accumulation effects.

Here three different filter settings are composited together.

This is just one of the layers from the above video at higher resolution.

Material from the second video will most likely become the main foreground with the other composite being used occasionally. Because I'm rendering this at 1920x1080 this is currently a non-real-time project (about 1fps render time). At lower resolutions however this does work at a high enough frame rate to be useful. I'd love feedback and suggestions =)