Another open source robot arm has cropped up on Kickstarter, It seems to have 6 DoF which is nice. Surprisingly it uses brushless DC motors and Hypocycloidal gearboxes that they claim are backdriveable. This is a serious step up from the hobby servos many arms use but there are lots of tradeoffs with hypocycloids which need to be overcome. The motion looks a bit jerky right now as well, so I suspect some more work needs to be done either on software or hardware. All said though, the ambitiousness of the design and price point has me intrigued.