One such example of using an analog display was carried out by programmer and hobbyist electrician Cristiano Cesaretto. He grabbed a cheap old tachometer, usually used to display a car's engine revs, from eBay and then modded it to display his PC's CPU usage via a USB cable.
Christiano details how he achieved this mod on his blog, and you can find more general instructions over at DIY Life.
Check out the completed modification in action:
[Via Hack A Day]
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