@b0rk Not a fuzzer, per se, but I have used hypothesis in Python testing, and it definitely finds bugs and edge cases I wasn't considering when coding or writing test cases...
On that note fuzzing-for-equivalence is similar: check that two functions are equivalent by fuzzing something that runs both and crashes on different results.
It is a subset of property testing, and the subset of property testing that's easy to implement as a fuzz target is larger than this, but I've found fuzzing-for-equivalent to be useful and to be a good way to think about property-testing-like things done in fuzz targets.