Free chess piece graphics

I've been developing some chess software (more on that in the future...) and spent considerable time last night searching for public domain (or Creative Commons licensed) chess piece images. I found surprisingly little, so this morning I fired-up Illustrator and made my own.

The ZIP file download contains PGN images of the pieces in three sizes, as well as the original vector-based art. I release these files under the Creative Commons Attribution license, so you can do whatever you want with them as long as you give me credit.