Tiggerito - 9:00 am on Apr 1, 2012 (gmt 0)
While in Google Analytics I discovered a way to detect if your website is being framed.
If you add Hostname as a secondary dimension for your pages it will list the domain of the top most frame. i.e. it will be your website unless you got framed.
In my case I saw Google translation pages, social bookmarking systems and url shorners.