Take a dollar bill out of your wallet. How much is it worth?
Say "a dollar," and chances are, you're absolutely right. But it's also possible that the humble Washington in your hands is worth much more than the number at the four corners of the bill.
Check the serial number.
The Boston Globe took a look inside the world of rare-bill collectors who are all about "fancy" serial numbers. It turns out those eight-digit numbers can be attractive in all sorts of ways to collectors, who will pay top dollar -- no pun intended -- for bills that meet certain criteria.
So if you'd like to take advantage of this weird hobby by selling to collectors, which number combinations should you look for? The article lists a few, including:
Low numbers: 00000001 is most prized, but 00000002 to 00000100 are considered valuable.
"Ladders": A sequential serial number, like 12345678 or 32109876.
Palindromes: Say, 45288254 or 02100120. Collectors call them "radars."
Repeaters: Blocks of repeating digits, like 85858585, are nice. A perfect sequence like 33333333 is even better, and known as a "solid."
But those aren't the only varieties that interest serial number connoisseurs. Dave Undis, who runs the site CoolSerialNumbers.com and has an extensive collection himself, details the various types of numbers that his fellow hobbyists will pay big bucks for.
Note that the actual denomination of the bill doesn't much matter to the collectors, since it's not like they're going to spend it. As such, it seems you'll get the most value in trade if you find the weird serial number on a lower denomination -- getting $200 for a dollar bill is a lot more profitable than the same amount for a hundred dollar bill. And $200 is hardly out of the question: The article cites a 77777777 $20-bill that sold for $528 in 2009, and other bills that sold in the thousands. Undis' site has many bills for sale in that range -- a hundred with the "solid" 11111111 going for $4,000, for example.
Speaking of Benjamins, collectors will be especially keen to get fancy numbers of the long-delayed new hundred-dollar bill. So the first time you get your hands on one of the redesigned hundreds, take a quick look at the serial number before you stick it in your wallet. The little green digits might not matter to you, but they matter to someone -- and that could mean a pretty penny for you.
Matt Brownell is the consumer and retail reporter for DailyFinance. You can reach him at Matt.Brownell@teamaol.com, and follow him on Twitter at @Brownellorama.