We are a couple of weeks away from getting our newly designed $100 bills, and when they arrive on October 8, some will actually be worth $1,000 ... or more.

No, the government isn't slipping in an extra zero. But it is including, as always, an eight-digit serial number. And as the Boston Globe explains, currency collectors will pay big if the numbers are "fancy." That's the collectors' term, not the Globe's, for serial numbers that fall in a number of categories: there are "low" (00000001 through 00000100), "ladders" (43210987), "radar' (43788734), "solids" (33333333), and "repeaters" (82118211). Then there are random ones: 31415927 (pi) or 07041776 (read that as 07/04/1776).

The low number ones are among the most valuable, with new $100 bills with 00000001 expected to sell for as much as $15,000. (Before the serial number you'll see one or two letters; these indicate which Federal Reserve bank issued it. As such, there can be more than one bill in any denomination with the same serial number in a given year.)

So how do you get your hands on one? It helps if you have friends in high and very secure places. Bank employees, especially vault workers, are typically able to swap out a normal bill for a fancy one, says the director of currency of a Dallas auction house, and since bricks of money are marked with the serial number range, they can spot the bills fairly easily.

CoolSerialNumbers is looking to buy these bills.