A certain politician did a successful coming soon page. It was actually a relaunch. He was out of the current race and they did not only a redesign of his site, but a redesign of his entire political purpose (for the present). They advertised about the countdown to all those on their emailing lists and it created a stir, with many hoping for a big announcement on the day the unveiling was to happen. Sad to say it was a bit disappointing, but the effect of the countdown was certainly successful, in my opinion.