“Millions of people now spend several hours a week immersed in ‘massively multiplayer online role-playing games’ (MMORPGs). These are often Tolkienesque fantasy worlds in which players battle monsters, go on quests, and build up their virtual power and wealth. Some synthetic worlds are deliberately escapist; others are designed to be as lifelike and realistic as possible. Many have a strong libertarian bent.” But there’s another side to this: economics.