America's Most Expensive License Plates

Don't throw away that old tag. It might be worth thousands of dollars.

In Pictures: America's Most Expensive License Plates

The deal went down in a Wendy's parking lot in Biddeford, Maine, nearly eight years ago. Huddled between a Subaru station wagon and a 1961 Cadillac Coupe de Ville, two men made a seemingly lopsided exchange: One left with $40,000, the other with an old license plate.

It wasn't just any piece of metal, but a 1921 Alaska plate. One of only four known to exist, it is the holy grail of a little-known hobby: license plate collecting. These vintage plates aren't street-legal, though some states allow them to be used on classic cars of corresponding years. But the rarest ones are nearly priceless to thousands of license plate collectors around the country. Tim Stentiford, editor of PLATES magazine, estimates that the 1921 Alaska tag is worth $60,000 today.

In Pictures: America's Most Expensive License Plates

"These plates are so rare that people who own them like to keep it fairly low-profile," says Stentiford, who has over 17,000 plates of his own. "They don't want the paparazzi and the other plate collectors beating down their doors."

The 1921 Alaska isn't the only plate worth more than a new car. Two others include the 1912 and 1913 Mississippi plates, worth an estimated $35,000 and $50,000, respectively. Collectors didn't even know that the 1913 Mississippi plate existed until 1985, when Dr. Roy Klotz, Jr. unearthed it after someone responded to a classified ad he'd placed in a Jackson newspaper looking for old Mississippi plates. Only two are known to exist, making the 1913 plate more valuable than its 1912 predecessor.

In the years since Paris issued the first license plate in 1893, tens of billions of tags have been produced and discarded. Like postage stamps or baseball cards, they've become a niche commodity. Countless groups, formal and informal, have sprung up to link collectors.

The world's largest is the U.S.-based Automobile License Plate Collectors Association (ALPCA) with 3,000 active members, established in 1954. Smaller groups like the Netherlands' De Nummerplaat and France's Francoplat exist abroad. Some countries allow individuals to trade street-legal plates; these fetch obscene amounts of money in places like Abu Dhabi (Click here for the most expensive.)

American hobbyists usually focus on collecting an entire "run" of plates. Some try to get a plate from every state, but with a unifying theme. Most typical is the "birth year run," where a collector casts about for plates from all 50 states issued in his or her birth year. A handful hunt special designation plates like Livery, Truck, Wrecker, Dealer and the like.