The Spirit of the Liturgy by Pope Benedict XVI, written when he was still "merely" Cardinal Ratzinger. It's an interesting book, focusing not so much on the theology of the liturgy nearly as much as how it should be done. Should the priest face east? Should the people? Why do we kneel and when should we do it? Interesting answers to those questions.
I also started De-coding Mary Magdalene: Truth, Legend, And Lies
by Amy Welborn, which coveres what we know and what we don't know about Mary Magdalene, which is an especially important question in light of the DaVinci Code's false claims about her. She discusses the Gnostic Gospels and why they're not a reliable source of history or Christian beliefs., where the association of Mary Magdalene with the woman caught in adultery came from and many other interesting questions. By no means, is it a scholarly work; it's meant for a popular audience so is really just an overview and summary of much reseach others have done. It's a book that can be finished in an afternoon, but you can still learn a lot. Definitely recommended.