xmlTreeNav is a XML viewer with several features.
It can show the differences between two XML files
(by using software based on the libxmldiff
project). It can also perform XPath searches,
"local XSLT" display, easy tree navigation, and
more.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.