Embedded systems engineer Mathieu Stephan proposes a novel means of home device control with Whistled-- a small hardware and software package allowing one to control CE products by, well, whistling at them.
The device combines a microphone, amplifier, driver, 3.3V voltage regulator and open source software in a hacker-friendly printed circuit board. Users can program it to respond to different whistles, and a video shows Stephan whistling to switch on/off and dim lighting.
Stephan says the Whistled is easy to install (all it needs is the connection of 2 wires and a power supply) and has a 4.5m listening range via mic sensitive tuned to tell whistles from other background noises.