Do you really need that light on to not trip over your coffee table and break your leg? Let's find out, shall we? The Consumption Feedback Switch is a device that monitors your electricity usage. If it feels you're within your light quota when you flip on the lights, you'll see a small, harmless spark. But if you've been one of those dolphin-unsafe villains from Captain Planet, reading a few minutes too long at night, a gigantic stream of deadly electricity will mend your ways pending you not die.
Alright, we're actually not sure that you feel a shock at all since the word "spark" may have been the choice of a liberal Google translation denoting "small glow." But we'd recommend keeping wasteful electrical usage down just in case. [product via dvice]