In another life I was a researcher on gambling, and perhaps the most important public policy question that (legalized) gambling presents is regulatory: how are the games guaranteed to be "fair"? In Nevada, for example, the Nevada Gaming Commission oversees the casinos to ensure that the operations of the employees and of the technology (roulette wheels, slot machines) are, as their mandate from the legislature puts it, "honest and competitive." The point is not to protect people from making some bad bets (such as betting on a single number in U.S. roulette -- a 38:1 gamble that only pays 35:1), but to guarantee that the games are (a) run as they are claimed to be and (b) in the case of slots, not paying out less often than a certain floor percentage. Why think about this here? Well, with RMT now openly encouraged by the makers of some virtual worlds, can their players trust the 'house' not to skim a bit too much off the top?