>>105681166
>gravity batteries
There was a start-up making fucking flashlights on that concept. Apparently they finished elementary school because now they make an overpriced 3d-printed crank flashlight except instead of a crank it's a much less convenient pull cord. And of course, it disrupts the ever-powerful KEROSENE LAMP market.

https://deciwatt.global/gravitylight

Because apparently some retard hasn't seen the little crank-rechargeable flashlights you can get at any hardware store for 5$.