Lord, Save Us From Your Followers by Dan Merchant
If you're involved in discussions about politics, religion, ... actually, if you have heated opinions about anything, you should probably give this book a gander. Yes, its focus in God, religion, and christianity, but I think almost anyone can take something from this book.
His goal is to be a mostly silent observer, listening to what people on opposite sides of the line have to say about one another and the idea of the "Culture Wars." Merchant doesn't think he has all the answers, but he's pretty sure God does, and whether you believe or not, the author raises some excellent points about listening and perspective. Oh, and a reminder that we are all human, by the way.
This is a very successful book (in the author's goal, at least) and I'd recommend this to just about anyone who is willing to listen :)