Teen and 'tween social networking site and doll dress-up community Stardoll announced that it reached 20 million registered users since launching in 2006.

Backed by $10 million in venture funding from Sequoia Capital and Index Ventures, Stardoll has doubled membership since announcing in August 2007 that it reached its 10 million members registered milestone. The company also announced that it has experienced a 33% increase in monthly unique visitors and that it has so far sold over 208 million virtual items.

To celebrate its 20 millionth member, Stardoll is giving away 20 Stardollars, the site's currency, to anyone who log in within 36 hours after the site reaches the milestone. The company is also giving away twenty couture creations to thousands of its members through a lottery.