I wanted to advertise Steemit platform and I came with this idea after remembering a post I saw on reddit about churches advertising theirselves in fake banknotes. Here is the printable ad I created (I know my photoshop level is over 9000):
Those banknotes were made in an attempt to attract people into steem. The places where they were placed included a public library (in some tables and inside some books), a bar, a gas station and in some vending machines among others.
In the text it can be read (note that back side has been rotated 180º to make the text readable) "Bad luck, this is not a real banknote but if you still want to earn 10 true euros you can sign up for Steemit, a social network that gives you 10€ after registering and more money creating quality content. Scan the QR code to learn more"