Step 1: Materials and Tools:

Bill of materials:

- some wire for all the electrical connections

- copper wire (make sure its coated, the red insulated stuff will work also though, just no BARE copper!)

- 1mm aluminum sheet (size depends on your wristband)

- wristband (from an old watch or just a leather strap, modified ladies belt)

- disposable camera board

- 2 momentary switches

- old CD case

- 5-10 caps from cameras OR 1 big capacitor 350V 800uF

- 4mm screw aka projectile (make it around 10mm long, the coil 15mm long)

- LOT of patience and common sense !

TOOLS:
- drill (dremel will do)

- handsaw / jigsaw

- soldering iron

- hot glue gun + sticks

- sharp knife

- screwdriver

Step 2: The How-to-video Guide:

BE CAREFUL! Its high voltage!! Never touch anything with both hands, when you tested the circuit!

The charge can kill you or hurt you. Always short the caps with a "heavy" screwdriver or something.