Tthis is actually an event that happened to my father. When he was a child, probably around ten or twelve, his cousin and he slept on the fold-out couch downstairs in the living room. While everyone was sleeping, my father noticed that the medal bars in the window pane were lighting up and looked like electricity flowing through them.
The current (possibly it was electricity) formed into some kind of electric ball, then flowed through the living room towards the thermostat and sort of got into it and everything in the house went tranquil, the air-air conditioning went out, the lights, just everything. When everything returned to normal, my father and his cousin looked at each other in surprise and asked, “What, did you just see what I saw?”
They both happened to see the same thing, but here's the twisted part: my great-grandfather had died about a week earlier, and my father's cousin told him that he thought he saw their grandfather's face on a supposedly “floating ball.” To this day I am trying to figure out whether it was electricity or the possibility of my great-grandfather's last farewell to the living.