There are already a number of popular virtual worlds such as Second Life, There and Entropia Universe.

BBC: Screen shot from Metaplace

His Neverdie Studios, which employs 13 people and is situated on prime real-estate in the heart of Hollywood, is creating entirely new planets in the Entropia Universe.

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The hottest virtual market around today seems to be in Entropia Universe, a space bound MMO best known for having an actual working economy based on real money, which results in headlines like this.

FORBES: Virtual Entropia Universe Property Sells for $335K Real Dollars

This means that virtual items acquired within Entropia Universe have a real cash value, and a participant may, at any time, initiate a withdrawal of their accumulated PEDs back into real world currencies according to the fixed exchange rate, minus transaction fees, the minimum amount for a withdrawal is 1000 PED.

FORBES: Virtual Entropia Universe Property Sells for $335K Real Dollars