OSS is nothing really new anymore, even Microsoft announced 60% of their software (they use!) is OSS. But OpenSource Hardware is still fairly new, at least on a broader market. Over the years I read about various initiatives to launch this kind of products. I believe only geeks and hackers are attracted by hardware they can build, program and configure to their needs and ideas. Many years back I did some electronics (during my studies), but often started from the scratch with simple stuff to control household devices, as simple as dimming the light with a remote, etc.
I came across the Arduino board which gives you a micro-controller platform that you can connect to your Windows, Mac or Linux desktop to program it and let it run independently. It is all open and documented, you can control something simple like a LED but can go to the extend of reading acceleration, temperature, controlling cameras, an almost infinitive field of appliances. Google for Arduino projects and you find amazing stuff, built on top of a 29$ device.
I recommend at least some basic knowledge of electronics, but even without any clue, you can get started, there are plenty of books and websites with tutorials.