We've seen a lot of prosthetic and bionic arms and hands as of late. This latest one might just take the cake though. It is called the handiii and it is made by a company called exiii. It is an open sournce myoelectric hand which is controlled with a smartphone. It costs under $300 to make and can be programmed for the wearer. It also has replaceable fingers which can be changed out for fingers that can take on different functions. Read and see more at: http://3dprint.com/52935/exiii-handiii-prosthetic-hand/