Tablet PCs, Notebook computers and Netbooks are part of personal life. Screen time on these devices is anywhere between 2 and 6 hours and this too when on the move, with minimal charging. To be energy efficient to the maximum, simple functions such as the closing of the screen or a case should cut off supply to the screen and change the device state to a power saving mode. Due to the extremely competitive market of such devices, manufacturers need to come out with thinner and smaller models every year and are embedding batteries permanently into the enclosure with no option to have them changed. Furthermore, components being used on such circuits also need to be energy efficient to ensure maximum battery life. Reed Switch and reed-based sensors are inherently energy saving devices as they do not require power for operation and can reliably switch extremely low current signal loads in the range of few femto-amps. Even when the sensor is in an actuated state, the resistance across the contacts is so low in the order of a few milli-Ohms, that unnecessary battery drain is avoided. All one needs is a reed sensor mounted on the control circuit with a tiny rubber or plastic magnet on the screen door, to help save power.