Drupal adding some sort of hash on end of clean URL? The site is working normally otherwise, but junk like this: #.ULQf0OOe90s is added onto the end of every URL.

Any ideas why this might be?

Thanks
This seems very similar to this topic in Wordpress:

http://wordpress.org/support/topic/random-hashtag-strings-added-to-url-in-firefox

Did you had the "Share this" module installed?