Hand Possesses Potential
From: Servo Magazine - 08/2011 - page 22

In an interesting meshing of robotics and prosthetics development, Japanese
researchers from Tokyo University working in conjunction with Sony
Corporation have created an external forearm device capable of causing
independent finger and wrist movement. Introduced on the Rekimoto Lab
website, the PossessedHand (as it's called) can be strapped to the wrist like
a blood pressure cuff and fine-tuned to the individual wearing it. The
PossessedHand sends small doses of electricity to the muscles in the forearm
that control movement, and can be "taught" to send preprogrammed signals that
replicate the movements of normal wrist and finger movements (such as
plucking the strings of a musical instrument). 

Though the signals sent are too weak to actually cause string plucking, they
are apparently strong enough to cause the user to understand which finger is
supposed to be moved. Thus, the PossessedHand might be construed to be more
of a learning device than an actual guitar accessory. 

Currently, devices that do roughly the same thing are done with electrodes'
inserted into the skin, or work via gloves worn over the hand - both rather
cludgy and perhaps somewhat painful. This new approach in contrast is said to
feel more like a gentle hand massage. 

Though the original purpose of the PossessedHand seems to be as an aid to
help people learn to play musical instruments - something that has inspired a
bit of criticism from the musical community due to the fact that nothing is
actually learned when using the device - the Hand basically becomes an
external part of the instrument, while the brain remains passive. It seems
clear the device could be used in many other ways. For example, it could be
used by hearing people to assist in speaking with deaf sign-language users or
to help people type who have never learned how. Or, perhaps more importantly
to help paralyzed people or those suffering from a stroke. 

Links:
Rekimoto Lab
http://lab.rekimoto.org/

PossessedHand demo
http://lab.rekimoto.org/projects/possessedhand/

Hand-hacking lets you pluck strings like a musical pro 
http://www.newscientist.com/article/mg21028186.100-handhacking-lets-you-pluck-strings-like-a-musical-pro.html