Some other prominent Web Traffic Analyzers like to Zoomstats are:
But Zoomstats is under the GPL(GNU Public License) meaning it's completely free and Open Source. Therefore you can avoid the high prices of other Web Traffic Analyzers.
ZoomStats is a software for every usage. It will have to support every database known to the world right now. It is not a very hard thing to do: PHP supports quite a lot of databases today and, thanks to the Object Oriented Design, ZoomStats will be able to work with each one of them. Early versions will support MySQL, PostgreSQL, and Oracle.
There are 3 ways to get the client's data:
Examining your web server's log
The installation process is simple and currently documentation on it (if you encounter any problems) is being written, just in case. ZoomStats will have a feature that warns the user when a newer version is out.