The IncPy idea is very neat. A cursory look at the github repository indicates that it is released as a modified version of CPython 2.6.x. This is unfortunate, because it guarantees that it will soon be obsolete. Ideally it should become a PEP and be implemented by multiple Python implementations; how difficult would that be? From the repo I cannot see how much extra code is involved here.

Another thought I had is whether you could implement this in pure Python using the introspection features of the language. Finally I was reminded how with certain languages such as Lisp, there is this notion of an "image", which is a dump of the state of the interpreter. Does that achieve the same end as this? If so, wouldn't that be a much more general solution?