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Don’t be so smug the next time you walk away from a trade show with a mountain of free flash drives. They require electricity too, and with this simple USB power monitor you can calculate just how much those supposedly ‘free’ giveaways are contributing to your monthly power bill.
The monitor sits between a USB port and a given device, and reports the voltage and current being used in either direction. It’s a great way to calculate just how big a backup battery you might need to keep your phone running, or whether or not you should actually leave that novelty wriggling USB tentacle plugged in all day long. [Smartronix via The Gadgeteer]
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Surely the volt/amp detection circuit and the lcd screen is using more power than the pen drive? also it’s at most 2.5watts (if within the usb standard)
If the image is anything to go by, I don’t think I’m too worried…
So you could spend $50 on this to see that your usb stick costs 50p if plugged in for the entire year.
Most useless product ever.
Also how dumb you would be to buy one.