AWstats web reporting tool

AWstats is a free and useful web site statistics reporting tool. Written in perl, it is quite customizable. Some of the prominent features are:

One tool for analyzing web, ftp and email traffic
Can generate reports via command line or as a cgi script. Reports directly generated from command line are limited in layout and features. e.g it doesn't support frames
Allows reverse DNS lookup to get hostnames, where possible instead of IP
Allows restricted access via IP and username
Filtering based on IP, browser and page visited is possible. Regular expressions are supported
Permits filtering of different sections of report
Provides limited customization of web report. Items such as HTML head section, end section, logo and logo link, colors and layout can be modified
Has a extensible plug-in based architecture. Third-party plug-ins, which extend core features are available
It is possible to create new charts by defining rows and columns
Configuration changes can be made easily from a single text configuration file