Rusty cars that could be worth millions

This Ford GT40 roadster prototype, one of only five like it ever made, was thought to have been ripped apart and sold off in parts decades ago. Then, in 2006, it was revealed that it had been resting atop an old mattress in a London warehouse with many of its parts, indeed, gone. Restored, it's now thought to be worth between $500,000 to $600,000. The car will be auctioned off at an RM Auctions event in Cernobbio, Italy, later this month.

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