Depending on how thorough you want to be, don't forget evercookies http://www.schneier.com/blog/archives/2010/09/evercookies.html http://www.schneier.com/blog/

Depending on how thorough you want to be, don't forget evercookies http://www.schneier.com/blog/archives/2010/09/evercookies.html http://www.schneier.com/blog/archives/2010/09/evercookies.ht... http://arstechnica.com/security/news/2010/10/it-is-possible-to-kill-the-evercookie.ars http://arstechnica.com/security/news/2010/10/it-is-possible-...