For those of you who didn't see it, Burger King (via their agency Crispin Porter + Bogusky) launched a Facebook app at the beginning of this year offering a free Whopper to anyone who 'sacrificed' 10 of their friends by deleting them. The best bit was, if you'd been sacrificed an alert would appear in your newsfeed, letting you know that you now ex-friend valued a burger more than your virtual friendship.
Sadly, owing to privacy concerns (that we can't quite work out), Facebook has decided to shut the app down. We doubt Burger King is especially concerned though seeing as 233,906 friends were sacrifieced by 82,771 people in under a week, coupled with the massive PR the stunt achieved.
Read more here.