St. Francis of Assisi and his trip to Cairo to meet with Sultan al Kamil is a very interesting chapter in a very ugly story (the Crusades). Part of what I like about it is that it involves dialogue between two people who were passionate about what they believed, while still being able to respect each other, speaking and listening.
A nice article on this is located at http://www.sufiways.com. The article is:
MMM -- Mission Musings 