Pimping Out Movie Maker?

Hey guys, it occurs to me this morning that if iMovie comes with a selection of animated backgrounds for use on a Mac in order to create something such as this lovely example from Laurie Cabot, HPs ( http://www.youtube.com/watch?v=EAmiOfwTEoM ), than surely there are websites on-line that allow for one to either create, download, or customize animated backgrounds similar to those used by iMovie, only to be able to download them and import them into Movie Maker as with any recorded video; after all, there seem to be many very similar such capabilities as when creating customizable MySpace layouts, or even slide shows, for example. So, why NOT animated movie introductory backgrounds, too? It would seem illogical for there to be a vacuum of applicable free websites, then. So, I was wondering: Has anyone ever heard of any such sites that are tested-and-true? :o) Heck, it makes little sense to think that there aren't any free sites available to really pimp-out one's home videos!