The Faithful Departed by Philip F. Lawler

An insightful analysis of the collapse of Catholic culture, with particular attention to the Boston archdiocese

The Devil's Delusion by David Berlinski

This is Berlinski's answer to the "new atheists" (Sam Harris, Christopher Hitchens, etc.) Berlinski is something of an acquired taste (which I acquired long ago with his A Tour of the Calculus) and sometimes writes in an overly florid style, but in this book, his prose is disciplined and a joy to read.

Death in Holy Orders by P.D. James

P.D. James has an excellent reputation, but I only made it halfway through this book before dropping it in boredom. I'm still an Agatha Christie fan when it comes to mysteries.

The Nature of the Universe by Lucretius

Lucretius was an ancient Roman who lived in the century before the birth of Christ, an atheist and an Epicurean

De Cive (Citizen) by Thomas Hobbes

Hobbes's development of civil society out of the state of nature.