I created a very brief animation using Fractal Design's Poser2 a few years ago. Since I am unable to create a flowing cape right now, instead I added a Clark Kent figure for visual interest. Below is only a still preview, since the actual animation is 519KB.
(It is a big file which may take a while to complete, but give it a chance...)
This file will repeat several times-though you have to allow time for it to fully download first. Once loaded, it plays at a nice speed and is only seconds long.
