Relax 

Relax is a free, multi-platform web server log analyzer for tracking which search engines, search keywords and referring URLs led visitors to the web site. Frequently updated parser module recognizes hundreds of search engines.
log log analyzer log analyser log analysis referer statistics stats tracking search engine keyword url search traffic perl

Relax for Windows 

Relax for Windows is a free, web server log analyzer that tracks which search engines, search keywords and referring URLs led visitors to the web site. Frequently updated parser module recognizes hundreds of search engines.
log log analyzer log analyser log analysis referer statistics stats tracking search engine keyword url search traffic windows