Jessica at Nervous System writes:

I created this design yesterday for the Shapeways SIGGRAPH competition which asked designers to submit any design that costs less than $200 to 3dprint. Our submission is a sculptural vase generated by reaction diffusion, a process which simulates how chemicals diffusing across a surface react with one another to produce stable patterns.

made with Processing, rendered in Sunflow, polygons reduced to 500,000 for 3d printing with Meshlab. all free open source software!