Carl's Jr., a west-coast burger franchise, ran a limited online offer during a Laker's game that gave special ticket holders a URL and passcode to get a free burger coupon. Within 48 hours, the recipients had spread their good fortune all over the internet, resulting in Carl's shutting down the offer.
Source Article:
http://blog.wired.com/27bstroke6/2009/01/online-burger-p.html
