A Russian security expert has demoed a tiny electronic device, dubbed ‘USB Killer v2.0’, which can kill a computer – or, in fact, just about any device with a USB port – within seconds of it being inserted.

The tiny object, which looks just like a USB memory stick, draws a small amount of power from the host device and stores it in an internal capacitor until it reaches 220 volts.

This high voltage is then sent back into the host via the USB port and the charge cycle begins again. Within a second or two, the power surge ‘fries’ components on the device’s motherboard, killing it stone dead.

The designer of the USB Killer, who goes under the pseudonym Dark Purple, shared details of the project on Habrahabr, a Russian IT and computer science blog.

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A test video – which you can see here – shows him inserting it into the side of a working laptop. The screen goes blank after less than two seconds, following a short frazzling sound.

Dark Purple says it’s extremely unlikely that the hard disk was affected. So there’s a small silver lining: the USB Killer 2.0 could kill your computer, but your family photos and other important data could still be rescued.

There’s nothing to suggest that Dark Purple designed the device for malicious purposes.