TUAW reports that a hacker installed the Couch Surfer browser on a jailbroken Apple TV and used it to play an HTML5 version of BlackJack.

Circulating rumors suggest Apple may open up the Apple TV and add support for the App Store in a future firmware update or possibly a future model. Until that happens, these HTML5 apps could be an easy way for users to get their application fix.

  HTML5 game running on Apple TV