Wondering exactly who some of these people are who you befriended on your page?

Well, oddly enough, that could be a good combination these days.

Burger King this week launched an application called the Whopper Sacrifice. Taking its name from the fast food company's well-known burger, the Whopper Sacrifice rewards who delete 10 of their online friends with a coupon for a free Whopper burger. The application can be downloaded from either Facebook or from the .

"What would you do for a free Whopper?" the site asks hungry visitors. "Now is the time to put your fair-weather web friendships to the test. Install Whopper Sacrifice on your Facebook profile and we'll reward you with a free flame-broiled Whopper when you sacrifice 10 of your friends."

Burger King, which last year released the BK Polarizer widget that gauged people's political views, is trying to ride Facebook's popularity wave with its primary customers - 18-to-34-year-olds who chow down on fast food burgers.