I'm currently doing a couple of 'Ice Cave' renders, and an animation is in the making. I'm not sure if it's going to be any good, because rendering refractive materials is not only extremely slow, but also prone to a lot of unwanted artifacts. But let's put the problems aside for a moment.
I'm going to use the Ice Cave examples to explain something about fractals that I've been thinking about for a while.  I'll try to not to get too technical, and anybody with a mild interest in rendering or computer graphics should be able to follow it.