While the entire system is still prototypical, it currently works "over a 35 square kilometer area in Stockholm, " and designers are currently testing interest in other locales throughout the UK. Personally, we can't wait to see the variations in storylines while cruising down the 101 versus the pits of Hell's Kitchen, but we'll probably just wait for third party reports of the later.

ENGADGET: Backseat Playground to integrate GPS into in-car gaming