Was it a capacitor the size of a water tower?My electronics teacher said a friend of his touched a screw driver to a big capacitor in a large speaker/amplifier one time... The guy was thrown across the room and the end of the screw driver was melted.
I would imagine it takes a lot of energy to melt the end of the screw driver and throw a guy across the room (heat makes gas rapidly expand?). Capacitors don't store a lot of energy. They just can discharge very quickly. Their energy density is a few orders of magnitude smaller than that of batteries.