Open source hardware isn’t just a cute little idea that some scruffy hobbyists and smarmy entrepreneurs are pushing for their own reasons. Real live scientist-types are using it to solve important problems.
Imagine you have a something happening in one place and you want to measure how long the effects take to get to another place 10km away (light, sound, the Higgs boson, whatever). Well, it turns out you are going to have a pretty tough time figuring out exactly how long it took for the effect to travel from one place to another. Timing is kind of a really really important issue and getting it right requires specifically designed systems.
White Rabbit is what CERN came up with to measure things at exactly the same time even when they’re really far apart. It is being used mainly for physics projects, but they carefully designed the system to be generic and open so that it could be used for pretty much anything.
The WR project “provides deterministic data and timing (sub-ns accuracy and ps jitter) to around 1,000 stations [and] automatically compensates for fiber lengths in the order of 10km.” It is also, “completely open.”