I purchased a defibrillator capacitor on EBay and have upgraded the old 2.4 KV can crusher to a 5 KV can crusher. I added a voltage doubler on the output of the Microwave Oven Transformer (MOT) to get almost 5 KV. The defibrillator capacitor is rated at 30 uF at about 5 or 6 KV. Can you imagine hooking that up to a person?
The video is now up on YouTube at: http://www.youtube.com/watch?v=SbjXFbuCvqE
Here is the guts that are inside of the 5 KV Can crusher. The 1 uF 2 KV capacitor that was removed from a microwave oven is mounted on a piece of plastic to insulate it from the chassis.
Here is the schematic of the 5 KV can crusher's power supply. The 10 Meg resistor in the voltage divider fried because it could not handle 5 KV. So I replaced it with 10 x 1 Meg ohm resistors. Technically I think it should have been 9 x 1 Meg ohm. The defibrillator capacitor was only 30 uF, I wanted to get a 100 uF capacitor that was on sale on EBay for $150 but the price was a little high.