Did you ever wonder where banknotes travel? Where the bill comes from that you've just received, or where it will go once you spend it?

I just came across this website:

www.eurobilltracker.com

Apparently, tens of thousands of people have entered the serial numbers of more than a million Euro banknotes they have spent, as well as the location where they did so. Whenever a banknote is entered again, it generates a "hit". There's statistics, maps, etc.

Though none of the 5 banknotes that I've entered has produced a hit so far...