Pycro is a library that attempts to compile python bytecode to i386 machine code.
To attempt to make some very small standalone python programs. And because it's funky ;-)
So what can it do?
All the python files immediately under the 'samples' directory can be compiled.
PyPy is an attempt to create a python runtime written in python, whereas pycro attempts to statically compile python programs to machine code. In that sense pycro could be compared to the the restricted execution portion of PyPy, or ShedSkin.
Because I wanted to write the program! No intention of taking over the world; it's just a bit of fun.
It's not optimised at all! And it won't be for a long time (if ever)... That said, for code that manages to compile (and actually run!) it'll likely run a lot quicker then native python, plus not need any sort of a runtime.