Hi, LWN.net had a article on the development of Unladen Swallow that aims to speed up CPython. http://lwn.net/SubscriberLink/332038/675304c610f0e34a/ The project link is: http://code.google.com/p/unladen-swallow/ At least on my Linux system, Numpy does run without any test failures. It appears slightly faster than my distros Python2.5 (the installation overwrote my local copy of Python2.6 that I built myself so I can not say if is faster than that). Bruce