I once got a novelty advert in the mail around 2000 with a  flashing LED, I ripped off the carboard and put the LED and battery holder in my junk drawer. I totally forgot about it.  Years later when the power went out from a storm I looked over and saw that the drawer was glowing red. Sure enough that led was going constantly for over 10 years.,(reply>), @demonsluger Maybe the inside of the drawer was only visible from a specific angle and they indeed never had a blackout,(reply>), im more amazed that you never had a blackout or turned the lights off for over 10 years