I just heard about this program, the first in the U.S. and the second one in existance (Ulm Germany was the 1st). I got these pictures while at RRsmart today. Sounds like a pretty cool program.
According to earth2tech.com
Daimler will have car-sharing program in Austin, Texas. Daimler will roll out its “mobility concept,” car2go, in Austin this fall following the expansion of a pilot program in Ulm Germany.
Austin will have 200 Smart Fortwo cars with micro-hybrid drive in the city. Once registered, you can pre-book the cars online or via mobile phone, or check out an available vehicle in person. When you’re done, you can return the car to any unoccupied parking space within a set operation area. Charges will apply but it's calculated by hour and min.