Pretty interesting and I often wonder how things get started up and sometimes the people who started them end up not getting the credit.
I have always wondering about printing fake bills for fun like that as well and the legality behind it. I believe there was a 3 dollar bill that had Bill Clinton on it and that always made me wonder because some people wouldn't realize it wasn't real.
Clearly a 0 is pretty obvious that it has no value but I would also be a little worried about it. Hahaha