Fractal Fr0st is an application to view and modify fractal flames in realtime, as they are being rendered on screen.
Fr0st allows you to visualize the results of an iterated funcion system as it is rendered. This is a very early version of it, with lots of planned funcionality missing. The only controls so far are moving the mouse to change the location of the active transform and the left and right keys to switch between transforms. It's hard to explain in non-technical terms, just try it out. If you know how to use Apophysis, you can let your own flame be rendered by Frost.