Home-made spot welder. Made using a microwave oven transformer re-wound for high current.
Puts out around 800 amps at approximately 1.6 volts. Good for crafts and repairs.
I used it for crafts using stainless steel banding cut-offs. They made nice Christmas ornaments and other do-dads.
Included is a good supply of those bands. Repair most any sheet metal thing.