Rated 5 out of 5 stars
I recently firmed up all my security settings to stop being tracked and force https use etc. This included changing 'network.http.sendRefererHeader' in Firefox to stop the referer header being sent.
Unfortunately this stopped some sites from working, in my case I couldn't log into my BBC user account as it need the header for verification.
Added RefControl, added the BBC site (forged header), and it's working again.
Simples. Very happy!