Visions of Chaos is by far my favourite Fractal generating software.
It has a plethora of fun fractal and fractal related simulations and generators. The features are too numerous to list. You need to try it to believe it. It also has many pre-made colour templates and a template editor.
Even if you do not understand the math, like me, it is easy to create amazing images of all sorts.
This software is a must to try.
You can not lose. It is free!