The latest KiXtart version (4.66) can be downloaded from this site.
Unfortunately, KiXtart.org, though kept up to date again, is almost impossible to use due to its frame in a frame in a frame.... (at least, in Firefox)
Version 4.66 supports COM automation of the script engine itself, which means you don't need to rewrite your KiXtart scripts to use them in VBScript.
Read the "readme" for more details.
More documentation, in CHM format: KiXhelp453.chm.
Not entirely up to date, but easier to navigate than the (up to date) Word or PDF documents.
KiXtart, was created by Ruud van Velsen of Microsoft Benelux, but is not officially supported by Microsoft.
It was originally intended as a scripting language for (Windows) logon scripts.
Up to version 3.* that was its most powerful application.
However, over the last year, and especially since version 4.*, it has become much more powerful and versatile.
I have used it often for its features, many lacking in batch, or because of its more-or-less Windows version independence.
A good example of a feature not available in Windows batch is a GUI style message box.
I have often used NET SEND to display a graphical message box, but KiXtart' MessageBox() function is much more versatile.
User input, and hiding the console, are also very well handled in KiXtart.
Or how about finding a user's primary group in NT 4?
It is possible using KiXtart's @PRIMARYGROUP macro.
I have converted many scripts using WMI from VBScript to KiXtart version 4.*.
With my WMI Code Generator creating WMI queries for KiXtart has truly become a piece of cake.
With KiXtart version 4.* you can define your own functions, also called UDF (User Defined Functions). This is an extremely important improvement!
Other improvements are the new FOR loops, several new functions and macros, and last but not least COM automation.
Archived older version can be downloaded from www.kixtart.org/downloads, the official KiXtart home.
A lot of valuable information can be found in the forums of the KiXtart Bulletin Board.
From my former colleague Adriaan Westra, several examples of KiXtart scripts.
Amongst others a script to list all file versions in a directory (Lstprtdrv.scr); we used it to check the printer driver versions installed at the office.
Choose Tips & trics, Kix scripting.
Some tools for KiXtart developers: