A couple guys argue that quantum fluctuations are relevant to most macroscopic randomness, including ordinary coin tosses and the weather. (I haven't read the original paper yet.)
If false, this could be easily falsifiable with a single counterexample, since if true, no coin tosser, human or robotic, should be able to do significantly better than chance if the toss is reasonably high.
EDIT: according to this
[...]
the premise has already been falsified.
If it's worth saying, but not worth its own post, even in Discussion, it goes here.