GM rushed work on a new API to get a popular Volt owner site back on road. "The Web services supporting OnStar's applications for the Chevy Volt were hacked by developer Mike Rosack to create Volt Stats, a site for owners to brag about their mileage. Now, OnStar has given him a new, approved API.
You probably don't think of your car as a developer platform, but Mike Rosack did. A few days after buying his Chevy Volt, Rosack started slowly mining his driving data. But he eventually revved up his efforts and created a community platform for drivers to track their own efficiency. Today more than 1,800 Volt owners compare stats with each other, jockeying for position on Rosack's Volt Stats
A good article that goes a bit in depth on VoltStas as well as the new OnStar API. Kudos, Mike!