Playing guitar [update]
Recent advances to do the really important things in life not only cover exploits regarding bike riding.
Also, people were at it trying to improve their guitar picking.
From http://satechie.co.za/2015/02/03/3d-printed-prosthetic-hand-lets-teen-play-guitar: (C) Copyright SA Techie / David Venter
A company called 3D Gluck Columbia [twitter] [youtube] custom 3D printed this arm for him.“We wanted to create something that was useful and that could increase Diego’s quality of life,” said 3DGluck co-founder Andrea Monroy [facebook].
So far, it is somewhat obscure what the background or future of that company is.