Just read Bernie's comment about the Quake engine being used in a non-violent way. My vision of the History game was to use a 3-D engine to explore and interact with a historical environment, kind of like Everquest, except set in Renaissance Italy. The players could become involved in multiple aspects of the society (economic, cultural, social, etc.). If used with K-12 students in the classroom, the city could be inhabited with real cyber actors who take on the role like the actors who inhabit the Plymouth Plantation in Massachusetts. The class could go on a real virtual field trip to a time period where they normally would only access in a book or through a film.