Facebook's developer platform has been used for a zillion marketing campaigns so far, but this one is actually dead-on hilarious.
Fast-food chain Burger King has created "Whopper Sacrifice," a Facebook app that will give you a coupon for a free hamburger if you delete 10 people from your friends list.
Burger King has put out some interesting campaigns as of late ("Whopper Virgin," "Subservient Chicken"), but this one piques our interest because of how gleefully it pokes fun at our social-networking obsessions. "Now is the time to put your fair-weather Web friendships to the test," the Whopper Sacrifice site explains. "Install Whopper Sacrifice on your Facebook profile, and we'll reward you with a free flame-broiled Whopper when you sacrifice ten of your friends.
The funniest part: The "sacrifices" show up in your activity feed. So it'll say, for example, "Caroline sacrificed Josh Lowensohn for a free Whopper." Unfortunately, you can't delete your whole friends list and eat free (however unhealthily) for a week. The promotion is limited to one coupon per Facebook account.