Show us your home made tools

I'll snap a little tomorrow, but I build a "remote starter"
Two lengths of wire (red and black, doesn't get any fancier then that) with an alligator clip on the end, attached to a simple push button

(The push button was left over from a new gun modified
It was an electric belt fed nerf gun
Real cool, but the motor always ran so it gave away your position
I bought the push button and installed it in the handle, so you squeeze the handle to turn on the motor and the pull the trigger for the kill

Anyways, stuff all that in 8 inches of left over PVC pipe and it even has a handle