Pranav Mistry gives an incredible overview of his gesture technologies in his TED Talk, The thrilling potential of SixthSense technology. It isn't until the end of the talk that he discloses a main reason for his work. He wants to make sure society doesn't end up as a bunch of machines, sitting alone and talking to other machines.
Mistry starts with the idea that the technology itself isn't important to the individual, but the information that the technology can bring. Further, interacting with the technology physically doesn't need to happen if the devices can follow your gestures.
http://www.ted.com/talks/pranav_mistry_the_thrilling_potential_of_sixthsense_technology#t-226157
The video is full of demonstrations of the sixth sense technology, from its origins as mouse rollers and a collector bracket to the necklace apparatus used in 2009. Using physical gestures to control motion in the digital world was the beginning.
Writing post it notes that uploaded themselves to a program was a great idea. A map of an airport was configured so that placing any object on top of the map would show you where to buy the object.
Allowing the pixels trapped inside devices to escape was the big breakthrough for Sixth Sense. Using gesture sensors attached to a user's fingers, information could be projected onto any surface. My favorite example of this technology is a 'square' gesture made by the user to take digital pictures and save them on the device.
This talk in ancient when framed in terms of technological change and internet time. In 2009 Pranav was an MIT grad student, and in early 2012 he again partnered with TED. The sixth sense code was released as open source so that any developers could create their own devices.
Today Pranav is the head of Think Tank Team and director of research at Samsung Research America. His website is full of projects that he has completed, both with and without the sixth sense technology.
http://www.ted.com/talks/pranav_mistry_the_thrilling_potential_of_sixthsense_technology#t-226157