Hey an idea doesn't have to be original, or even practical, to still want to make it. As long as you find it useful, learn something new, and are having a good time, power to ya!
I think it's cool you got this rendering behind the desktop!
As a suggestion, it might be neat if you could set up your layers with transparent png objects, and then apply some animation over time to the layers. That way you could create neat live backgrounds using static images and your application instead of having to have/obtain a gif.
Either way, keep it up!