Danny Taylor is a genius. He is going to teach an entire generation of children to turn the lights off when they leave the room, and he’s going to do it in a time-honored way: by traumatizing them.
Taylor has designed this dimmer switch which smiles when the lights are off and frowns when they're on:
Lights on = bad. Lights off = good. Simple. Kids with this in their bedroom are going to be followed for the rest of their life with a vague sense of unease if they leave the room and the lights are still on. Turn them off, and -- aaah, that feels better right? Now the light switch loves you, because now you deserve it.