SixthSense is a wearable gestural interface device by Pranav Mistry,

[kullatiro]

http://en.m.wikipedia.org/wiki/SixthSense

The SixthSense prototype comprises
a pocket projector , a mirror and a
camera contained in a pendant-
like, wearable device. Both the
projector and the camera are
connected to a mobile computing
device in the user's pocket. The
projector projects visual
information enabling surfaces,
walls and physical objects around
us to be used as interfaces; while
the camera recognizes and tracks
users' hand gestures and physical
objects using computer-vision
based techniques.[1] The software
program processes the video
stream data captured by the
camera and tracks the locations of
the colored markers (visual
tracking fiducials) at the tips of the
user's fingers. The movements and
arrangements of these fiducials are
interpreted into gestures that act
as interaction instructions for the
projected application interfaces.
SixthSense supports multi-touch
and multi-user interaction.

[kullatiro]

sixthsense code
An open source project that allows
people to create their own
SixthSense Device

http://code.google.com/p/sixthsense/