The Corsican authorities have passed a law requiring anyone who wants to buy a house there to have lived on the island for at least five years. The move is a response to people from mainland France and abroad buying up properties as holiday homes, causing prices to spiral. As a result, many Corsicans can no longer afford to buy property there. But now a few communities are fighting back, and threatening to enforce pre-emption rights -- including the village of Cuttoli near Ajaccio, the birthplace of Napoleon.