PORTLAND, Ore. -- "Fire in the hole!" shouts Ron Hoodenpyle, covering his ears and stepping away from a brand-new Mazda 3 he just wired with special detonators. Suddenly, all six of the car's airbags explode at once.

Within hours the metallic blue sedan will be drained, gutted, squished and shredded -- one of thousands to meet the same fate here. The cars are so new, most don't even have 10 miles on the odometer.

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