I'll say it again. Flying Swordsmen was illustrated almost completely with PD images. I'm thankful for the art donated by Dylan of Digital Orc and of course Daxiong for donating that awesome cover image. I did a couple things myself (the frontispiece and map). Most of the images came from PD sources, though. And I love the Public Domain.
So here's a lazy-ish post of some cool PD images from my hard drive. Just because.