To be honest I don't read a lot of books anymore, I mostly read online now. I do collect old books though... so I'll share the last book I bought : ) It's a Webster's International Dictionary. The information that you can find in an old dictionary far exceeds what you find in a modern day dictionary. They also have practical information in them, not just words and their meanings. They're really fascinating to read!
Here I am with it... sorry I didn't get it out of the cabinet, it's heavy!! : )