Verbal Acrobatics: Motion posters

Found some cool examples of animated posters which I feel help me to get an idea of what's already out there in terms of posters which at first glance look pretty standard but have an animated layer to them too.

http://www.reviewstl.com/wp-content/uploads/2010/07/Ignition_Saw3d.swf

Most of them tend to flash .swf files which I find a bit sluggish, wouldn't a high quality .gif be better and less annoying? I was planning on converting my printable posters into animated .gifs