(MONEY Magazine) – Worried about coming face to face with a carjacker, as more than 25,000 Americans have since 1991? Then you might be a candidate for the latest in automobile antitheft devices (suggested retail price at auto specialty stores: $160 to $399 plus a $100 to $200 installation fee), which give you the option of abandoning your vehicle when a carjacker approaches and then they disable the auto once he is driving it. After the crook flees the stopped car and you or the police find it, you deactivate the electronic box hidden inside and drive away. Clifford's Blackjack ($160) shuts down the engine when the car slows to three or four miles an hour if the system has not been deactivated by tapping in the owner's private code. Blackjack also sounds ear-piercing horns and blares lights if the car is not deactivated upon entry. You launch Audiovox's Posse ($399) by calling the company's 24-hour toll-free phone number after a carjacking. Your command to stop the car is then sent via satellite anywhere in the U.S. In less than a minute, the car's lights flash and the horn blares. When the carjacker turns off the ignition, he prevents the car from being restarted. When you get your car back, you punch in the Blackjack password or call Posse's 800 number to make the auto drivable again.