Following my recent post on a free open-source 64-bit Python distribution for Windows, I was able to create the project (WinPython, "a portable scientific Python distribution for Windows") and write some code to generate a portable Python distribution from scratch (actually from existing distutils packages).
I've just uploaded WinPython v188.8.131.52beta2 for both 32-bit and 64-bit Windows platforms.
WinPython has its GoogleCode project and everything is ready for downloads, discussions, bug reports and feature requests.
Enjoy! (I hope)