Use your old AA batteries (will be 3x D-Cell long for flashlight)

This is a thing in progress... (picture is outdated / parts updated 2019-03-02)

Will become a 3x D-cell flashlight thingy for your empty AA batteries. Forgot to explain, but this will become 2x D-Cell length for 6 AA batteries and the 3rd D-Cell length will contain some electronics.

Named a Joule-Thief by this guy (hope I can find him):
https://www.youtube.com/watch?v=mcDgOGC5Lcc

Many people think this is magic etc... etc... but it's not... This will be the first time a Joule-Thief is