Piwik(http://piwik.org/) is open source self-hostable web analytics tool (like omniture or  google analytics). To integrate piwik with mediawiki, I customized the existing Google Analytics mediawiki plugin (http://www.mediawiki.org/wiki/Extension:Google_Analytics_Integration) to work with piwik. To include the extension in your wiki,
unzip the file, and deploy the piwik.php extension file into WIKI_INSTALL_DIR/extensions/. Then include the file in your LocalSettings.php, using:

require_once("extensions/piwik.php");


Download piwik extension