An actual 3d fractal flame, hovering over an ocean. It's actually a composite of 3 renders, one of the 3d fractal, one of an ocean at the same angle, and a 2d version of the fractal used to cast reflections in the water.
This one has been sitting unfinished for a year, because the gray blast wave didn't like mixing with the fire, and kept crashing the computer. I figured out it would render once per loading of the image, only crashing the second attempt. So I reloaded after each test render, which let me finish.