Whether you own a personal stereo system that offers nothing more complicated than cd playback and radio stations or a DVD server with complex recording and storage functions, it's important to keep electronics dust-free and clear of debris which might block vital ventilation holes. In addition to keeping electronics safe by keeping them clean, unplugging electronics from the wall when they are not in use is also a great way to ensure no power surges impact the devices. This also allows for a rather significant savings of power as most electronic devices continue to use electricity even when they are off but plugged in.