We covered a similar DIY version of this device, it turns off something plugged in when it detects your PC is off –
“Many computer peripherals use power even when they are turned off. The Mini Power Minder communicates with your PC via USB so when you start up or shutdown your computer, power to the secondary outlet starts or terminates at the same time. You’ll control all your peripherals in one easy step! To control multiple devices, plug a power strip into the secondary socket and use it as an extension for several devices.” [via] – Link.
- HOW TO – Peripheral power control with screen saver – Link.