This nefarious little device will kill any devices with a USB that you plug it into. Apparently billed as a penetration testing device, sounds like orc mischief to me.
Once plugged in, the USB kill stick will charge internal capacitors and cycle releasing 200 volt bursts. Knocking out any unprotected electronic devices connected to it.
If you are completing your collection of over-the-counter James Bond gadgets, you might need this. Not many other reasons to own I can see.