The appeal of online virtual worlds such as Second Life is such that it may trigger an exodus of people seeking to “disappear from reality,” an expert on large-scale online games has said.

Virtual worlds have seen huge growth since they became mainstream in the early years of this decade, developing out of Massive Multiplayer Role-Playing Games.

And the online economies in some match those of real world countries.

Their draw is such that they could have a profound effect on some parts of society, Edward Castronova, Associate Professor in the Department of Telecommunications at Indiana University, told the BBC.