People lucky enough to have got their hands on one of the first of the new, polymer, £20 notes are already cashing in - selling them for more than £30 each on eBay.
And so far, all the ones to be snapped up at more than their cover price have serial numbers that start the same way.
When the new plastic £5 came out, people rushed to get their hands on them to see if they had one of the coveted AA 01 serial numbers.
People lucky enough to find them were then able to sell them on eBay and Facebook Marketplace for hundreds and hundreds of pounds.
But that's not what's selling with the new £20 - instead it's the "AB" £20 notes that people are cashing in on.
While the Bank of England has confirmed to Mirror Money that there are some AA notes out there, none have been tracked down yet and put up for sale.
However, 18 of the new £20s with an AB prefix to their serial numbers have already sold on the auction site - most going for more than £30.
One person has sold two "AB" notes for £75 (£32.50 each), another has sold 10 at an average price of £31 each and a third sold two sets of three for £99.97 (£33.32 each).
The better news is the Bank of England told Mirror Money that some AA notes would definitely be entering circulation - giving people another chance to find a £20 worth more than £20.
And they could pop up anywhere, with the Bank itself admitting it has no idea where they will be distributed as it simply doesn't store its notes by serial number.
What they'll go for if you find one is anyone's guess right now.
