Inspired by Mattystereo's ideas for Today the Eagle Awakens, this puts a twist on the standard "switch continents" concept (I've seen quite a few North America as South America, and Europe as Asia): have them rotate in roles. So, for example:
Africa as Asia: Dominated by the ancient Egyptian civilization, once upon a time challenged by a resurgent Axum that adopted Asian practices. To the south, challenged by a federation of Bantu and Kongo cultures that were once under Indian domination.
Asia as Europe: Although once dominated by the Chinese Empire, after the fall of the empire, Asia has been divided into various powerful, warring states. Reached the height of its power in the 19th century, when Asian powers had colonies the world over.
Europe as Africa: Long considered a dark and cold continent, Europe was the home of the mighty Roman Empire, but the age of Roman dominance has long