MrSeb writes "Microsoft Research, working with the University of Washington, has developed a Kinect-like system that uses your computer's built-in microphone and speakers to provide object detection and gesture recognition, much in the same way that a submarine uses sonar. Called SoundWave, the new technology uses the Doppler effect to detect any movements and gestures in the proximity of a computer. In the case of SoundWave, your computer's built-in speaker is used to emit ultrasonic (18-22KHz) sound waves, which change frequency depending on where your hand (or body) is in relation to the computer. This change in frequency is measured by your computer's built-in microphone, and then some fairly complex software works out your motion/gesture. The obvious advantage of SoundWave over a product like Kinect is that it uses existing, commodity hardware; it could effectively equip every modern laptop with a gesture-sensing interface. The Microsoft Research team is reporting a 90-100% accuracy rate for SoundWave, even in noisy environments."