Matthew Green starts his 2005 Ford Escape with a duplicate key he had made at Lowe's. Nothing unusual about that, except that the automobile industry has spent millions of dollars to keep him from being able to do it.Read more at Cnet
The systems reduce car theft, because vehicles will not start unless the system recognizes a tiny chip in the authorized key. They are used in millions of Fords, Toyotas and Nissans.
All that would be required to steal a car, the researchers said, is a moment next to the car owner to extract data from the key, less than an hour of computing, and a few minutes to break in, feed the key code to the car and hot-wire it.
Security of thief-proof car keys cracked

A graduate student at Johns Hopkins University has cracked the security of the "immobilizer" anti-car theft systems from Texas Instruments.