Quinn Norton's written a stupendous piece for Wired News on a new open-source prosthetics movement started by a Iraq-war veteran upper-arm amputee named Jonathan Kuniholm, who has vowed to produce a prosthesis "that's so cool, somebody with two arms would want an amputation to get one."
Kuniholm was an engineer before his Marine reserve unit was sent to Iraq, where he lost his arm to an IED. His engineer/design partners in North Carolina worked with him to improve the nonfunctional smooth plastic prosthesis he was issued by the VA, making substantial improvements over the basic design. Then they decided to open up the designs to help other amputees. The site has grown into a collection of prosthesis hacks that includes mounting a Spider Man fishing rod on a child's prosthetic arm.
All this week, Garry Trudeau has been running a Doonesbury series about BD, the football jock/veteran amputee just back from Iraq, who goes to a motorcycle shop with his prosthetic leg to get the man there to "pimp his gimp."
Founded last year, the nonprofit Open Prosthetics Project applies the ethical and intellectual property foundation of open-source software to the task of building better artificial limbs. The project releases its experimental designs to its website in the public domain, free for anyone to use, forever. Anyone can download the STL files, tinker with them in CAD software, and submit them to a rapid manufacturer, such as a prototyping 3-D printing company.
This lets anyone turn out a customized prosthetic device without incurring tens of thousands of dollars in production costs. A user with a few hundred dollars to spend can be holding the physical reality within a week, though the post processing would still require some expertise...
Open Prosthetics' experimental design incorporates both modes in one hook, using a pin/spring/cam set-up controlled by the intensity of the wearer's shrug: A limited shrug momentarily opens or closes the hook, just like the traditional design, while a full shrug acts as a toggle, reversing the hook from open to closed, or visa versa, and leaving it there until the next actuation.
They've built and rebuilt two versions of this positional hook, and they have a working prototype of the entire limb made from LEGO Technic parts. (This video demonstrates the strength difference of the two modes in picking up a small object.)
Update: The Lizardman sez, "This reminded me of Amina Munster, a Suicide Girl who had her prosthetic leg pimped on an episode of Inked. I remember seeing the episode being stunned when she handed the leg to the artists to be 'tattooed' and mentioned how much it cost - he seemed suitably awed as well. Here's an NSFW interview from BME/News which includes her.
Update 2: Nick sez, "I work on a public radio program, The Story: with Dick Gordon. We recently aired an interview with Jonathan Kuniholm and Chuck Messer, two founders of The Open Source Prosthetics Project. The same show also features an interview with Robert Haag, a man who was motivated to design prosthetic devices--including a screw-on fishing pole--for his son Michael, who was born without a left hand. The show aired on August 17, and can be heard here."