Has anyone seen one lately?

Maybe 10-15 years ago someone or a group was stamping $1 bills (USD) with a red where’s George stamp that had a website along with it. You would enter the location you got it from and its serial number and you could see where all it had been before it came into your possession and where it went after you used it if you were smart enough to write the serial number or take a picture of it. I haven’t seen one in years has anyone seen one recently or have they gone the way of the dinosaur. I think of these often and thought this would be the perfect place to ask.