All -
the PediaPress.com wiki-to-PDF extension and collection manager is now running on:
http://en.labs.wikimedia.org/wiki/Wiki_to_print
This wiki includes content from en.wikibooks, so should be a nice playground.
We're not announcing this super-widely yet to get some initial feedback, but please do get the word out in the Wikibooks community, and report issues on the talk page. :-)
Thanks! Erik