In George Jetson's world - where technology showers, clothes and feeds its owner in a matter of seconds - a computerized car that can turn itself on and off and rent itself out to consumers might not seem that far-fetched.

In 21st-century Baltimore, though, it's a different story.

Rick Whipp is trying to marry those two worlds with a technology that turns a car window into a touch-pad screen used to rent the vehicle and enable its ignition.

His company, Automated Car Rental LLC of Indiana, is aiming at a niche market of drivers who will opt to pick up their rental cars the high-tech way, just as George Jetson might have imagined.

"They can be rented unattended," Whipp said

The idea is to park the cars in places where mainstream rental agencies are tougher to come by. Places such as auto body and repair shops, time shares, businesses that have corporate accounts for rental cars, marinas or retirement communities.

Whipp is testing two of the rental cars, dubbed Touch'n Go cars, in Baltimore, where they rent for $25 an hour, or no more than $55 a day, and $275 a week.

Here's how the cars work:

The rear driver's-side window serves as a touch-screen, which users tap to start the system. The screen shows the user how much fuel is in the car and the cost of a rental, and the user plugs in name, address, date of birth and credit card and driver's license numbers. The system then provides a loss of damage waiver and collects information about any damage to the car, checks the credit card and license information, and unlocks the car and enables the ignition.

"The ignition is enabled only when the car is unlocked by the authorized user," Whipp said.

To turn the car off, the user gets out and punches a personal password into the window screen. The password can be used to enable and deactivate the engine and lock and unlock the car until it is returned. When the car is returned, it calls someone to clean and refuel it, and sends a receipt via fax or e-mail to the user.

Jack Brenn and his wife, Irene, of Florida used a Touch'n Go car while visiting friends on a boat docked at the Lighthouse Point marina in Canton, where the two rental cars in Baltimore are being parked.

"We needed a car simply to drive around," Brenn said. "It was our first time in Baltimore, and we just wanted to see the area."

The Brenns rented the car for three days, using it to go to dinner in Little Italy, shop at the Inner Harbor and tour Fort McHenry.

"I thought it was great," Brenn said. "There was no hassle, and it's very convenient and very quick."

That's what Dan Naor likes about it too.

Naor, a partner at Lighthouse Point, said visitors who are docked at the marina or staying there temporarily in apartments often ask about cars. Before, Naor's employees would call a rental car agency for them.

Now, with Touch'n Go, they send visitors out to the parking lot without having to worry about insurance, liability or extra manpower, Naor said. "What we like about it is, there's really nothing to do," he said.

Automated Car Rental has been developing its system for nearly three years and testing it for about 10 months. An avid boater, Whipp decided to keep two cars in Baltimore near his boat at the Lighthouse Point marina while the other eight are being tested in Indiana.

The system is not without problems. Service is spotty in the marina parking lot, so the cars there are being manually rented. But Whipp said his company is switching to a more reliable system in which signal strength won't be a problem.

"Any time you're using wireless technology, you're going to have problems like that," Whipp said. "There are ways to get around them with software, and we are currently enhancing our software to get around some of those issues."

Bill Leslie, who teaches a course in the history of automobiles at the Johns Hopkins University, said the idea makes sense for some drivers, but not for everyone.

If people calculated how much their cars cost compared to the price of renting one only when it's needed, most would opt to rent rather than buy one that would sit in the garage depreciating, Leslie said.

But it would be tough to market Touch'n Go cars as an alternative to owning a vehicle, he said, because a car is "one technology more than any other that we give a personality to. We give it a gender, we talk to it or we curse at it."

Whipp is marketing his cars to the occasional renter. Agencies that close at 6 p.m. or 8 p.m. and are losing overnight rentals might use his technology, he said.

He is also hoping that car rental agencies will become partners with Automated Car Rental, leasing the company's technology, installing it in their cars and leaving the vehicles where they can rent themselves.

Automated Car Rental plans to take Touch'n Go to market by the end of the year. Next year, it will start TelGo, a similar system that lets users rent cars through their cell phones.

The company is owned and funded by Whipp and his brother, though the two are working to bring in outside investors. Whipp, 40, who also owns airplane charter and leasing companies, came up with the idea for the high-tech cars when he and some guests docked in the Florida Keys after being at sea for several days and couldn't get a rental car delivered to them. Instead, they were told they would have to go to the airport to pick it up.

"We didn't want to wait for a taxi and then have to take a taxi to the airport, and then take the car, and then use the rental car," Whipp said.

Whipp solved the problem by riding the motorcycle on his boat to the airport and leaving it there. But from that experience, compounded by similar incidents at different venues, a new company was born. Whipp began asking around, wondering whether others felt the way he did. He found that the answer was always yes.

"I'd ask other people in the marina, 'Would you rent a car if there was one here?'" Whipp said. "And they all said, 'Yeah.'"