My other blog Discoveries & Oddities from the Digital Library collects unusual books from around the Internet - all public domain that can be downloaded for free and legally. Not quite something for everyone but lots of things for many people, particularly if you have slightly off-center interests.
Recent entries include:
Missing heirs to the French throne
Victorians looking at dinosaur fossils
Poetry parodies with kittens
Accounts of the Great Chicago Fire
18th century guide to getting rid of vermin
Wild illustrations of purported demons & magical beings
How to build shacks and shelters
The first book in English about Zen
and so much more......