Edit 2015 Jan
Tyring to find the source we remixed this from - can't find it; it's gone from thingiverse?
We wanted to print the fantastic Duchamp Chess by Scott Kildall and Bryan Cera in very large pieces - some of the overhangs were getting to be a problem at 300-400 percent so we started adding self supporting walls for filament based printers.
If anyone else is interested in the other pieces, we can upload them.
For those who asked, the material is Purple Translucent Natureworks 4043D from Ultimachine. Printed at 0.2mm, 80mm/s, 15%infill, although this piece will most likely come out allright with 0 infill.
As promised, here are the rest of the files.
Added a picture of the Knight at 200Percent, printe on the left in regular Natureworks PLA and on the right in ColorFabb BronzeFill.