Moreover, if two worlds compete and one has more players than another, wouldn’t t everyone have an incentive to join the larger world, so as to enjoy the larger network of society, communication and entertainment that it affords? Might such network externalities lead to a domination of this market by one player?For example, some network games such as lotro gold, runescape gold, guild wars gold etc. There are reasons to expect, however, that this market is not likely to be monopolized. First, there seems to be a great diversity of tastes for the different features of a world. Mr. Bird may want to be on Pluto, while Mr. Castronova prefers medieval Britain. One of the major attractions of life mediated by avatars is the anonymity it affords, and anonymity requires a person to have exit options: other worlds to escape to if one s reputation in this one gets unpleasant. Perhaps to savvy game developer could make a world so large and varied as to provide the essential minimum level of entertainment and anonymity to a sufficiently large number of people, so that membership in that one world becomes optimal for all. This seems unlikely, however, given that there is a marginal cost to creating and maintaining game content. Moreover, there are no economies of scale on the supply side to match the increasing returns on the demand side (Liebowitz and Margolis, 1994). Production of game content and its maintenance are both labour-intensive activities. One It could perhaps increase production of content by allowing other producers (say, by opening game code to the public), but continued control of the world being created would be problematic. On the whole, it seems very unlikely that one developer could produce a world big enough to monopolize the market. A second reason involves congestion. Virtual worlds are virtual because they are online, but they are worlds because there is some physicality to them.