Over at Wintery Knight's blog (a blog you should visit daily), he has a single post that indexes everything he has written on atheism and morality. Since morality has been the recent focus here at Reformed Seth, I'm recommending Wintery Knight's morality posts to you. His focus was whether atheists can adopt the moral point of view rationally, when it goes against their self-interest to do so. He actually surveyed atheists as well to get results for his study. It's very interesting.
Check out WK's study on atheism and morality here.