Rachel, our 9-year old, wanted some play money. So I took some real money and put it on our all-in-one laser printer. I intended to copy it on just one side, so it could never be used for real money.
What comes out of the machine? Red money! The printer was sophisticated enough to run that automatic counterfeiting routine.
I thought, “Oh no! Everything will have red on it now!” So I copied something else. The result was normal as could be.