For my bachelor thesis I designed a language focussed on concurrency, trying to use an event-driven approach without losing programmer control. See my thesis for the original design, and this paper for a formal description of PEP in ACP (the Algebra of Communicating Processes).
With my thesis came a Python simulation. The simulation comes with a few example PEP programs. There is also documentation.
The formalisations needed testing, which was done in a formal setting using PSF and in a parallel(!) setting using Go. There is a small report about my findings here.