Piwik é uma alternativa opensource ao Google Analytics, escrito em PHP e que utiliza MySQL como base de dados.

Piwik is a full featured PHP MySQL software program that you download and install on your own webserver. At the end of the five minute installation process you will be given a JavaScript code. Simply copy and paste this tag on websites you wish to track and access your analytics reports in real time.

Piwik aims to be a Free software alternative to Google Analytics, and is already used on more than 1,000,000 websites. Privacy is built-in!