I recently stumbled upon a website offering me a webhits counter absolutely for free. I managed to find out what platform is running behind it – Piwik.
Piwik is a downloadable, open source (GPL licensed) real time web analytics software program. It provides you with detailed reports on your website visitors: the search engines and keywords they used, the language they speak, your popular pages… and so much more.
Piwik aims to be an open source alternative to Google Analytics.