"Duhton" is a tiny (Lisp-like) language whose implementation follows the CPython interpreter. To play around with applying STM/AME techniques.
My public repository.
An adapation of PyPy's _ctypes package to run on top of cffi, on both PyPy and CPython 2.6-2.7.
A just-in-time compiler for Python. It is here mostly for historical reasons. It will never support Python 3, and is limited to 32-bit architectures.
A completely minor extension of CPython. If you build a CPython using the 'stm-thread' branch, you get a CPython 3.3.0a3+ with '_thread.atomic'. It works as described here: https://bitbucket.org/pypy/pypy/raw/stm-thread/... (but of course you don't get a GIL-free multicore Python). Similarly on the 'stm-thread-2.7' branch for CPython 2.7.x.