EFF - More privacy with HTTPS

Released in June as a public beta by the Electronic Freedom Foundation (EFF) and the Tor Project, the HTPPS Everywhere Firefox extension helps guarantee that your browser is using encryption when visiting 27 sites, including Google Search, Wikipedia, EFF, and many other sites that offer HTTPS.

To learn more and get HTTPS Everywhere:
https://www.eff.org/deeplinks/2010/06/encrypt-web-https-everywhere-firefox-extension