Public Domain Books on the Cheap

For those who might be interested: Public Domain Reprints offers a cheap-ish and easy way to get physical copies of hard to find/expensive public domain books you might need or want. I've been trying not to buy books since I have access to good libraries and I feel like I should use those resources first, but if you like to own the books you read this could be an extremely helpful resource. Let me know what you think of it. Also, Librivox is good for public domain audiobooks. I think I've shared Librivox with some of you before, I just wanted to put my recommendation out there for the world to see.