Safari Extension Hides You from Google and Facebook
tidbits.com/article/11660
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
Orbicule has released a free extension for Safari 5 that blocks several methods of tracking your behavior across multiple Web sites. The Incognito extension can prevent Google's AdSense and Analytics JavaScript from phoning back to the mothership. This incidentally blocks Google ads from appearing, but that's not the primary intent. The extension can also suppress all calls back to Google, and prevent Facebook and YouTube from working on sites other than their own.