This may seem like an odd recommendation, but I think The Autobiography of Malcolm X is one of the best books I've read. Easily the most gripping non-fiction.
Someone described it as illustrative of "the intellect of anger", and I think it fits. I also think, somewhat paradoxically, that such a precise and charismatic characterization of anger will make you more understanding of angry people.
Not odd at all - that was a great book about a great man. The most profound theme from the book, for me, was his quest for knowledge and self-education. And his commitment to live life as a reflection of his knowledge and beliefs, even when that meant complete and utter rejection of his previous life.
I'll second this recommendation - this book changed (and is still changing) how I think about some things, and it was hard to put down. In terms of developing empathy, I found the eloquent expression of anger over things I haven't experienced to be illuminating.
Plus, there are a lot of cheap copies floating around because it has been fairly popular since it came out.
Someone described it as illustrative of "the intellect of anger", and I think it fits. I also think, somewhat paradoxically, that such a precise and charismatic characterization of anger will make you more understanding of angry people.