Write something fun on it, like, "Clap when you walk past me ... When it dries, put it on the carpet to make your target think they have a mess on their hands. Not all good April Fools' pranks relate ...

"It made me curious about how the wave propagates when we clap our hands," Jung said. "Clapping hands is a daily, human activity and form of communication," Jung said. "We use it in religious ...