I got one of those a few months back.  I went to the website and entered my location tracking that specific dollar bill.
No one had reported it's location in about 3 years!!  After you pass it on, when someone else reports on it,
you will receive a notification from that website letting you know.  Sounds like fun to me!
I'm still waiting for a notification, as yet no one has reported it.

I think most people do not even notice the red stamping on the bill.

God bless,
Denise S.