Worldwide the idea is not new, but in late 2011 San Diego became the first U.S. city to offer an electric car-sharing network. It’s now flourishing.

Car2go, which is a subsidiary of Daimler North America Corporation, has a fleet of 300 of these smart cars in San Diego.

The blue-and-white minis look a little bit like robotic R2D2s. Cars are available 24 hours a day, seven days a week. It costs $35 to register for the system. After that, you pay thirty-eight cents per minute (the rental system has proven popular enough that it’s already undergone a rate rise, from thirty-five cents).

Costs: There’s a maximum of $12.99 per hour; $65.99 per day. There’s a 150-mile limit per rental.

But using the car all day is not the best application for this model. The system is best used for short hops. The autos help solve the “last mile” issue for residents.

“You can get people to some main hubs, but getting from those areas to a lot of places within the different neighborhoods is difficult,” says a spokesperson for San Diego mayor Jerry Sanders, who blessed the program. “Our idea with car2go was to help make that kind of urban lifestyle easier.”

The smart cars can be parked anywhere on city streets for free. You literally drop the car off at any metered spot near your destination. An online car2go map helps new users find a car near them.

And if one really feels like just going out for a joy ride, the minis top out at 65 mpg.