I haven't tried it but seems pretty cool. Then again I hate video chat. 

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Tinychat‘s super simple messaging service lives on the Web (and then some), but the fledgling company’s Facebook video chat application is clearly seeing some solid growth of its own.

The app is now the single most used video chat application on the Facebook Platform, with roughly 2.4 million monthly active users according to the application page.

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http://techcrunch.com/2010/12/03/tinychat-facebook/