Along the lines of the previous post, I've got one more for you. A few years ago, Kashi Canada launched a microsite in conjunction with a magazine campaign, if I remember correctly. The whole idea of Achieve Inner Kashiness was to take you through a three-minute breathing exercise.
Built in Flash, the site uses photography, moving type, and a soothing voiceover to guide you along the way. By no means is this cutting-edge use of the web, but I think it works. Given that Kashi positions itself in the realm of healthy living, being associated with a relaxing break in the middle of a hectic day is a really smart, subtle piece of marketing. On top of that, when's the last time someone willingly spent three minutes with your brand? How much would you have to pay for three minutes of uninterrupted TV time? In this case, that time is free.
Since the offline campaign ended, Kashi has added a link to the microsite on their Canadian homepage, allowing it to live on much longer than the magazine ads. Even if one person a day checks it out, it's worth it. Plus, if they like it, maybe they'll send the link on to someone else. You never know when something like this could go viral.