From Think Geek:
Sometimes it's fun to turn stuff off and on. But doing it everyday can get pretty tiresome and old. The Mini Power Minder can help. It has two built-in outlets - one that connects to your PC and the other to your peripherals (via a power strip). The Mini Power Minder also connects to your PC via a USB cable.
When you shutdown your PC the USB cable will no longer have power, letting the Mini Power Minder know to shutdown power to the secondary outlet. If you have your peripherals connected to this outlet they will be turned off along with your PC. The same process works when you power-up your PC.
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