The Mini Power Minder switches PC peripherals off automatically with the PC. The small power outlet is connected with the PC via a USB connection.

The Mini Power Minder has two built-in outlets - one that connects to the PC and the other to a power strip that connects to the peripherals. The USB Gadget also connects to the PC via a USB cable.
When the PC is powered down the USB cable will no longer have power, letting the Mini Power Minder know to shutdown power to the secondary outlet. The same process works when switching the PC on. Pretty neat.
Think Geek sells the Mini Power Minder for $15.99.

We reported about not so useful USB Gadgets in the past, but they are still fun:
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