To Mock a Mockingbird was a book that was sent to me and I enjoyed it. I can't fully do all of the puzzles, but they are for sure fun.

https://www.amazon.com/Mock-Mockingbird-Raymond-Smullyan/dp/...

One of my favorite books is To Mock a Mockingbird, by Raymond Smullyan (http://www.amazon.com/Mock-Mockingbird-Raymond-M-Smullyan/dp...). It presents itself as a puzzle book that teaches combinatory logic along the way. Not only is it lots of fun to work through the puzzles, but at the end, you have a pretty solid understanding of the lambda calculus.