As kids most of us have had our hands on some or the other sort of Lego kits. Although if you haven't been keeping up, Lego kits have come a long way. With the 'Lego Mindstorms' series you can almost build anything out of it, all you need is imagination and the right skill to assemble the parts.
A guy named Max Shepherd uploaded a video on YouTube titled 'Lego Robotic Arm' where he demonstrates his creation of what he calls a 'Lego Prosthetic Arm'. Similar to what the title claims the arm has a striking resemblance to the movements of a human arm. It has 12 degrees of freedom (DOF), just for your information, a normal human arm is said to have 7 DOF. The arms incorporates lego pneumatic cylinders. Although the movements are pretty slow but are fair enough to look human like. It can lift a couple ponds of weight and pour a drink for you.
The thing that sets this robotic human arms different from the others is; anyone can actually build one with the lego parts that have been used. Unfortunately Max Shepherd hasn't reveled a lot of details online except for the video and a little description, but anyways his work is really worth appreciating.
The controls for this arm are pretty rudimentary, this include a cluster of switches and joysticks. A 4-motor air compressor with pressure-regulation also made of Legos, but for the demonstration Max seems to have simply used hand pumps, that's what it says in the description of the video.
Here is the video of the Lego Robotic Arm/ Prosthetic Lego arm