I had an experience when I was a hardware engineer working in a lab that had been converted from previously being a machine room (for mainframes: raised floors, closed ventilation system). I was cleaning a prototype board with trichlorotrifluoroethane (or something similar -- whatever the solvent du jour was back then). The board had the typical green FR4 or Brobimer solder mask film. While engaged in this task I saw a little green dragon emerge from the board, chuckle, then blow a small flame from its snout. The whole thing was entirely realistic. The only thing that made me realize it wasn't real is I was pretty sure dragons don't exist.