Blue dot is a free GPL licensed Perl CGI tracking and web site activity measurement script which generates Apache combined style access log files. These log files can be analyzed with most standard log analysis tools to track site's popularity, referrers, hosts, etc. The logging is based on inserting a small piece of JavaScript or SSI code into every web page.

Relax for Windows is a free GPL licensed web server log analyzer. This tool analyzes which search engines, search keywords and referring URLs led visitors to the web site. Frequently updated parser module recognizes hundreds of search engines. HTML reports can be configured to include links to other web based keyword analysis tools.