For $3 each:
God is Not Great: How Religion Poisons Everything (hc) by Christopher Hitchens
The Great Deluge: Hurricane Katrina, New Orleans, and the Mississippi Gulf Coast (hc) by Douglas Brinkley
I've already read God is Not Great, but it's the sort of book I'd like to have in my personal collection as Hitchens displays a marvelous talent for rhetoric in writing this polemic against religion. You can read three excerpts of it at Slate.
The Great Deluge I've intended to read for going on three years. To get an idea of why I wanted to read this book in the first place, listen to Brinkley's erudite discussion of the subject with NPR (which also provides an excerpt.)