[clyfe]

Does any python implementation have non-GIL threading?

[kingkilr]

Both Jython and IronPython. PyPy probably will in the future, however its not a goal at the moment.

[tmorgan]

pypy also supports stackless style microthreads: http://codespeak.net/pypy/dist/pypy/doc/stackless.html but, yes, system level threads are GIL based.

[beagle3]

Also, long ago there was Prothon, which wasn't exacyly python but was very close, and didn't have a GIL. Unfortunately, it seems all source code drops of this disappeared from the earth, though you can still find some mentions e.g. http://blog.ianbicking.org/initial-thoughts-on-prothon.html

I don't remember how Vyper worked, but it might have abolished the GIL too: http://got.net/~landauer/sw/vyper_readme.html