If you have a $1 bill in your wallet, you might want to give it a second look. While it may not seem like a lot of money, certain $1 bills could actually be worth a whole lot more than their face value.

There’s a website called CoolSerialNumbers.com that is currently seeking out currency with “fancy” serial numbers. And if you happen to have one of these bills with a fancy serial number, you could potentially earn hundreds or even thousands of dollars by selling it to the website.

So, what exactly determines a fancy serial number? Here are a few examples to keep an eye out for:

• 7 repeating digits in a row: If you find a $1 bill with a serial number like 09999999, 18888888, or 19999999, you may have struck gold.
• 7 of a kind: Look for a bill with a serial number featuring 7 identical digits, such as 00010000, 00090000, or 90999999.
• Super radars: These are bills with serial numbers that read the same forward and backward, like 01111110, 10000001, or 80000008.
• Super repeaters: Keep an eye out for bills with a repeating pattern of 4 digits, such as 67676767.
• Double quads: Look for bills with a serial number that features two sets of 4 identical digits, like 11110000, 44440000, or 88880000.

And there’s even more to discover! Visit the website’s Want List to find out what other serial numbers they are currently looking for.

Can you believe it? Something as simple as a crumpled $1 bill could turn out to be a valuable gem. So, start checking your wallets, folks! Today just might be your lucky day.