There's still a lot we don't yet know about electricity. My father recalls, as a young boy, being in the living room of his house at the time during a thunder storm. They lived out in the country, and thus had lightning rods on the roof of the house. Lightning struck (I can't remember where, I'll have to ask him again). He claims to have seen balls of electricity/energy floating around the livingroom floor, until they hit a heating duct (which was metal and grounded) where they promptly disappeared.
Of course, this goes right along with the fact that what we don't know is infinitely greater than what we do know. I do not attribute his experience to anything supernatural, but rather to an aspect of electricity we have yet to understand, probably because circumstances need to be ideal and such ideal circumstances are rare.