You’d be forgiven for thinking Second Life is the only virtual world in town, from the acres of press hype in the last year. And there’s no doubt that Linden Lab’s world has deserved many of the plaudits (and fat marketing expenditure) coming its way, having been arguably the first non-gaming virtual world to excite mainstream attention.

But it’s not alone. Industry body Virtual Worlds Management recently estimated that 35 virtual worlds companies had trousered over a billion dollars of investment in the last year (although that research has since been questioned, with some of those companies not actually being involved in virtual worlds, and $700 million of the figure coming from one acquisition).