Do not attempt this instructable if you have no prior experience with high voltage, or if you have a dodgy heart.
Step 1: Tools and Materials
-A soldering iron
-a capacitor (see picture)
-a Flyback Transformer
-2 Kodak camera flash circuits
-a battery holder
-2 AA batteries
Step 2: Camera circuits
NB, having 2 charger circuits is not essential, one will do the job just fine
Step 3: The Flyback
Step 4: The Capacitor and Switch
Step 5: Last Step!
Now put the batteries in the battery holder, turn it on and push the switch while the 2 output wires of the Flyback are about 1-2cm apart, and, look! a spark!
This circuit also works with a car ignition coil in place of the flyback.