According to this Reuters article, upcoming MMO Lego Universe will use Lego bricks themselves as in-game currency and may head to consoles after an initial PC launch.
"The more a child plays, they collect more coins and more bricks. The more you play, the more you get to build things," said project head Mark William Hansen.
The piece adds:
Lego Universe will initially launch as a PC game, available in stores or as a download, and may eventually be available on other gaming platforms. It will operate as a pay-as-you-go subscription service at a "competitive price", Hansen said.
Worth a read, that, especially given the game's likely to be large beyond belief.