A Hong Kong firm has created a small device that can completely destroy a computer in just a few seconds by emitting a high electrical voltage through the machine's USB port.

The USB Kill 2.0 device is based on a proof-of-concept prototype that was invented and showcased by Russian security researcher Dark Purple in 2015. It can transmit 200V DC over the data lines of the host machine, and when this process is repeated multiple times within a second, it can cause the hard drive's controllers to be damaged to an extent that the data can never be retrieved again.

Apart from being in a desperate situation, or having a deep desire to ruin someone's day, USBKill.com says that the tool does serve an important purpose – testing computer systems for surge protection.

The USB Kill 2.0 device retails online for €49.95 (£42), and there is an additional Test Shield for €13.95 that enables security researchers to test it out on computers without having to destroy one every time the test is run. There's a discount if you buy both products together.

However, the product has proved so popular since it was launched in mid-August, that it is currently out of stock, and the firm expects to receive more on 14 September.

At the moment, only the latest line of Apple MacBooks are able to resist the power surge attack, because the hardware is designed to optically isolate the data lines on the USB ports. Therefore, all other computers in the world are at risk, because you can protect against malware, but you can't stop electricity.

And why on Earth would you want such a device unless you had evil intentions at heart? Well, do you have incredibly important data that could have disastrous consequences if it were to fall into the government's hands? Will the FBI, CIA, MI6 or GCHQ imminently be raiding your abode?

Imagine, if you can, that you're in one of those thriller movies where you're a whistleblower about go to on the run, and you know that a government agency is only a few steps behind you.

You've wiped your computers, you've hidden hard drives backing up your data in several secret locations, and maybe you've also sent your data to some other operatives as insurance in case of your untimely demise. But you know that computer wipes can be reversed, and you don't have time to smash your hard drive with a hammer.

You can hear the government's agents pounding up the stairs to your walk-up apartment, so quick as the flash, you pull out your USB Kill 2.0 device, plug it into your computer, jump out the window and shimmy down a convenient tree to the getaway vehicle waiting for you, while your trusty PC dies an honourable death, and the evil agents howl in frustration, having got into the room just a few moments too late.