Microsoft's Kinect motion sensor is now being trained in Japan to follow human tongue movement. Thankfully, a team of researchers at the University of Electro-Communications in Japan are working to right that wrong, developing a system that can detect tongue movements, using the relative positions of a user's eyes and nose.
Aside from the goofy nature of the concept, the idea behind this is to train the tongue for those with speech and swallowing disorders.
The feature has been demostrated with an Asteroids-like shooting game -- stick out your tongue to fire and move it left or right to adjust your aim. The whole thing has some practical applications beyond just making people looking goofy on video -- scientists see it as a way to train the tongue for folks with speech and swallowing disorders, one that doesn't require an unhygienic tongue attachment.
Here is the video demostrating Tongue interface using the Kinect: