the XML C parser and toolkit developed for the Gnome project (but usable outside of the platform). Code is portable (to Linux, Unix, Windows, embedded systems, etc.) and modular; most of the extensions can be compiled out
MSLU comes with licensing terms that are highly unfriendly to Open Source applications: although you can freely distribute unicows.dll with your application, your licensing terms must meet certain conditions that no Open Source license can.
it is possible to execute Python code at speeds approaching that of fully compiled languages, by "specialization". The current prototype operates on i386-compatible processors and shows 2 to 100 times speed-ups, depending on code.