I believe that it is called SUGARDANSEN! I think it's the best one i have ever heard. I want this on my Ipod Touch. This is the first AMV that I have seen that I can truly call a masterpeice. Plus, it is very cute.
Really surprised this isn't here. Truly unique take on AMVs and pretty much became one of my faves the second I started watching. It pulls of the documentary, "Behind the Music" amazingly. Stop reading and go watch.