I honestly have give it quite a bit of thought as to what it would take to start an open source hardware company. Everything has a user accessable API and the option to use their own firmware if they want.
The more important thing than hack-ability is that the product is rock solid.
That implies stuff like "there is one way to do it", "95+% branch coverage in unit tests", and "100,000-1M hours of automated stress testing of real hardware before shipping a new board rev."
