Python's NOSE testing framework has the concept of running multiple tests in parallel.
The purpose of this is not to test concurrency in the code, but to make tests for code that has "no side-effects, no ordering issues, and no external dependencies" run faster. The performance gain comes from concurrent I/O waits when they are accessing different devices, better use of multi CPUs/cores, and by running time.sleep() statements in parallel.
I believe the same thing could be done with Python's unittest testing framework, by having a plugin Test Runner.
Has anyone had any experience with such a beast, and can they make any recommendations?
Python unittest's builtin testrunner does not run tests in parallel. It probably wouldn't be too hard write one that did. I've written my own just to reformat the output and time each test. That took maybe 1/2 a day. I think you can swap out the TestSuite class that is used with a derived one that uses multiprocess without much trouble.