Well, now we know. Apparently your chances for being chosen to participate in the experiment were greatly improved if you were an internationally-known, Hollywood movie star with several million in the bank.
Autoblog Green says Pitt was spotted at Tuesday's "Ocean's 13" premiere in Hollywood driving a BMW Hydrogen 7, which could've increased the car's profile with the movie-star-loving public, though likely didn't considering its most identifying mark is a "Hydrogen" badge on the trunk. Members of the Brad Pitt Fan Club likely saw him exit a BMW 7-Series and thought nothing of it. But hey, at the end of the day he's still Brad Pitt, so all is right in the world.
[Source: Autoblog Green]