We went shopping today after we ran some errands and paid some bills. My husband had a dollar bill that he got in change, and the bill had "Where's George? stamped on it. Naturally, I had to check it out. The site tracks paper currency (US and Canadian) by the series and serial numbers. Only one of the bills I entered had already started being tracked...but it is kind of fun seeing how far money can travel. Now, I just wish it would s-t-r-e-t-c-h a little further.