You don't have to be a rocket scientist to make animated GIFS... all you need is a little imagination. Most of the animations at this site were created using store bought pieces of clip art and software that you can find as here. When you look at clip art, view it with movement in mind and what it would take to make it happen.

A simple mirror image of it might give a neat effect , sometime changing the colors will do the trick. But what ever you do, keep the files small! If it takes forever to load, your viewers will leave. If you use too many animations your page will act screwy. Always test your page on different browsers.