The Rocket-Powered Prosthetic Arm 
From: IEEE Service - 07/27/2010

Vanderbilt engineers trade in batteries for rocket fuel in the robotic arm
they are developing for amputees.  

Watch the video from this link:
http://www.ieee.tv/ieee_spectrum_reports/vanderbilt-engineers-trade-in-batteries-for-rocket-fuel-inrobotic-arm-they-are-developing-for-amputees-

Links:
Michael Goldfarb
http://frontweb.vuse.vanderbilt.edu/vuse_web/directory/facultybio.asp?FacultyID=21262

Gas-Actuated Anthropomorphic Upper Extremity Prosthesis
http://research.vuse.vanderbilt.edu/cim/research_arm.html