I just found this out. GM launches the largest car giveway in industry history. GM will be giving out 1,000 GM vehicles, prizes include a Hummer H2 sport utility vehicle, Cadillac CTS sedan, Saturn Vue SUV, Chevrolet SSR hardtop convertible pickup and Saab 9-3 convertible.
The campaign allows English- or Spanish-speaking consumers 21 years

or older to go to any GM brand dearlership, sit in a designated model, provide personal data using OnStar, and instantly learn whether they have won a free vehicle. (source provided by adage.com)
Odds are 1 out of 5,500. Much better than California Superlotto. You don't need to pay a single dollar bill.
So if you are over 21, head out there and why not take a chance. Nothing to lose except 30 minutes of your time (depending on the distance from your house to the dealership) and gas money.