The World’s Most Contagious Prank [VIDEO]
I wouldn't exactly call this a prank, but it is incredibly contagious.
I don't know what it is about a yawn, but whenever you see someone doing it, your body will do it. Watch how many people this guy gets to yawn just by yawning next to them. Try not to yawn...I dare you.
Did you do it? Did you yawn?