How economies spring up in extreme places from refugee camps to prisons. Ed Butler speaks to economist Richard Davies, author of a new book called Extreme Economies, who describes the economic activity in extreme places, from a Syrian refugee camp in Jordan to one of the toughest prisons in the world, in the United States. Former US prisoner Lester Young fill us in on how to trade behind bars. (Photo: A prison in Louisiana State Penitentiary, Credit: Getty Images)