That Is Currently Occupying My Thought Processes For Most of the Day: The End of Faith: Religion, Terror, and the Future of Reason by Sam Harris. He makes some difficult points and some outrageous-sounding claims, but the logic of his central position seems solid. Here are some tastey bits -
"The idea that any one of our religions represents the infallible word of the One True God requires an encyclopedic ignorance of history, mythology, and art even to be entertained... for there is no more evidence to justify a belief in the literal existance of Yaweh and Satan than there was to keep Zeus perched upon his mountain throne or Poseidon churning the seas."
"The belief that certain books were written by God... leaves us powerless to address the most potent source of human conflict, past and present. How is it that the absurdity of this idea does not bring us, hourly, to our knees? It is safe to say that few of us would have thought so many people could believe such a thing, if they did not actually believe it. Imagine a world in which generations of human beings come to believe that certain films were made by God or that specific software was coded by him. Imagine a future in which millions of our descendants murder each other over rival interpretations of Star Wars or Windows 98. Could anything - anything - be more ridiculous? And yet, this would be no more ridiculous than the world we are living in."
As I said, many rough points about the unsustainable influence of religious faith on what we think of as modern understanding. Somewhat perversely, I am now gripped by a real desire to read the Bible, or at least as much of it as I can manage to get through, just to confirm my own worst suspicions about this oddly powerful tome of myths and legends.
At the very absolute minimum, it will Get You Thinking.