Just how valuable is Facebook "friendship?"

Such is the question Burger King posed to Facebook users in its latest - but short-lived - advertising stunt.

Calling their new Facebook application the "Whopper Sacrifice," the fast-food chain asked users to "de-friend" 10 people in exchange for a free Whopper.

By installing the application on the Web site, users could trim their friend count and receive the coupon in the mail. According to Burger King, the final count of de-friended Facebook users since the application launched at the end of last month was 233,906.

The advertising campaign, developed by Crispin Porter + Bogusky, came to a halt Thursday when Facebook disabled the application.

While many found the choice easy to make because of their large lists of friends, others had second thoughts - each de-friended victim received a message indicating they were removed in the person's quest for a Whopper.

"It's so mean to just remove someone," said College sophomore Miranda Sturgis. "And besides, the burger is tasteless."

Wharton sophomore Ricky Katz agreed. "I don't understand BK's motive to have people de-friend each other," he said.

The blog Inside Facebook reported that Facebook became concerned that the application was violating users' privacy because of the "de-friending" notification.

"We encourage creativity from developers and companies using Facebook Platform, but we also must ensure that applications meet users' expectations," a Facebook representative wrote in an e-mail.

For part of yesterday, the application remained on Facebook but was disabled, rendering it useless for any latecomers looking for a free burger.

Burger King has generated considerable press and at times, controversy, for its recent advertising campaigns.

Sarcastically, the advertising blog AdFreak called the Whopper Virgins commercials, in which locals in remote places participated in a taste test between the Whopper and the Big Mac, a way to "enlighten the savages about the wonders of fast food."

The burger joint also developed and sold a Whopper-scented cologne called Flame that fortunately smelled nothing like an actual hamburger.

Despite the debate generated by Burger King, some students were indifferent about the whole matter.

"If you're really that hungry, I guess its okay," said Engineering sophomore Mitch Steinberg.