...which it increasingly is, as more and more 3rd-party services provide client-side javascript SDKs (head over to a billion young startup sites and see if they don't have a 'mixpanel' object loaded), as well as the telltale signs in markup and CSS. As well as API keys for various services hanging around in their client-side code, which is a little mind-boggling.

Anyway pretty brilliant idea to keep running stats on this stuff. $$$$$