I think you (the AJAXSLT developers) liked the experience of
implementing XPath from scratch. At least, I had fun working on my
project:

``Generative XPath is an XPath 1.0 implementation, which can be
adapted to different hierarchical memory structures and different
programming languages. It is based on a small, easy to implement
virtual machine, which is already available for different platforms,
including plain C, Java and .NET.''

XML Prague 2007 paper, slides, download:

http://xmlhack.ru/protva/prague07-generative-xpath.pdf
http://xmlhack.ru/protva/prague07-generative-xpath-slides.pdf
http://sourceforge.net/project/showfiles.php?group_id=138946&package_...

If you want an alternative, fully compliant XPath 1.0 implementation
for AJAXSLT project, you can try Generative XPath.

--
Oleg Parashchenko  olpa@ http://xmlhack.ru/  XML news in Russian
http://uucode.com/blog/  Generative Programming, XML, TeX, Scheme
http://olpa.livejournal.com/