Instructables user brunoip gave us permission to share his project for a rechargeable hand crank flashlight. This flashlight is unique in that it uses capacitors instead of batteries.
This DIY project takes on a gadget that can easily be bought in a store, but instead lets you use materials you already have to make something useful. It's also a great way to build your maker skills.
You will need:
Two LEDs, with their silver led holders.
An unipolar stepper motor with its reduction gear.
One or two broken PC motherboards, to remove the capacitors.
Two 220 ohm resistors.
A sheet of cardboard.
A small piece of plastic.
Four rectifier diodes.