Sometime last year Nintendo pulled off a one of a kind ad on Youtube where the video interacts with the whole page and tears it apart. Unfortunately, that ad has been discontinued. This was the page the ads was on if some of you still remember.
The most recent one is an ad from a Spain company; Acciona. The ad has something got to do with sustainable energy. It shows a guy breaking into pieces followed by the whole video screen actually cracking.
The link to the video can be found here: http://tech.geekpolice.net/2009/11/ads-tear-youtube-apart-again.html