I was wondering if such a low power usage device could be charged from button presses, but dismissed the idea as whimsical... and then immediately found another

I was wondering if such a low power usage device could be charged from button presses, but dismissed the idea as whimsical... and then immediately found another project on the front page that does exactly that! https://news.ycombinator.com/item?id=35077859 https://news.ycombinator.com/item?id=35077859 >We extract energy from (...) button presses of a regular Game Boy, using mechanical off-the-shelf button press harvesters. (...) The energy from the buttons is rectified, boosted, and stored in small capacitors.