from Engadget

Take a new ad from the restaurant formerly known as Kentucky Fried Chicken that premiers this week, in which a “secret” message is encoded such that it is only visible while the commercial is being viewed in slo-mo. Now the concept of hidden ads in-and-of itself seems quite effective–even the most die-hard commercial skipper still has to watch the screen to avoid missing the beginning of the next segment, so a fast-forward-viewable message is a likely evolution–but KFC is stepping it up a notch and actually providing an incentive for people to seek out the ad, offering a free sandwich to those who can regurgitate the hidden phrase