When Apple's Think Different television campaign first aired in September of 1997, the company was in dire straights (or, as we call it, "The Sculley Years"). To make a long and well-known story short, Steve came back, the company launched the enormously popular "Think Different" campaign with Chiat/Day, and that, true believers, was how Apple got its groove back.
LowEndMac takes a very interesting look at the development of that campaign, from the initial concept to the first broadcast commercial in '97. Some interesting facts include that Chiat/Day was given just 17 days to complete the project, and that Steve himself courted some of the people whose images were used.
Well done, Apple and Chiat/Day. We still love those ads.