The folks behind PhillyCarShare want a million Philadelphians to give up their automobiles in the name of saving the environment. The really crazy part? They just might pull it off...

...on a hot afternoon four months ago, Larry Shaeffer was driving east on Pine Street in rush-hour traffic when the cars in front of him started to swerve wildly in every direction. Larry hit the brakes till he was inching forward. He figured somebody had double-parked, blocking a lane. It happens a lot in Center City. But as Larry approached the disturbance, he could see that it wasn't a car at all. It was a woman. She was trying to cross the street. Larry looked closer. Something was wrong. The woman was holding her ground. Instead of stepping away from the cars as they swerved to avoid her, she was lunging toward them. The cars were juking her, like running backs - faking one way, then the other, trying to get by. It looked like the woman was trying to kill herself by getting hit with a car.

You've seen them everywhere. In prime parking territory on Center City streets, in Ikea parking lots, at the Wegman's in Cherry Hill. Hybrids, Mini Coopers, trucks emblazoned Philly CarShare. "Our wheels. Your freedom."

Where do they come from?