If you have a photocopier and a few currencies you can have a lot of fun with EURion:

- look up your local laws! usually you can photocopy money as long as it's shrunken / enlarged by a specific amount

- you can cover up everything but the EURion and see what it does to the rest of the copy

- you can cover up the EURion part of the bill and print out the rest

Again, particularly in the last point, be sure to look up local laws and set the printer scaling accordingly