List of funny chalkboard signs. Hilarious chalkboard signs, sometimes called sidewalk signs, with funny messages have become a trend on the Internet. Bartenders and restaurant owners are very witty people. They generally say clever things that are appreciated only in the moment. Thanks to social media sites such as Instagram and Facebook, these comedic anecdotes reach an audience of millions. Now there is competition to one-up each other and see who can have the next viral chalkboard sign. This has pushed creativity to another level.