Geniune anisotropic-scattering media clouds! I actually made a couple of alternate versions of this scene, the original was a perfect sunny sky, though I felt the more dramatic lighting and the addition of the moon would impress more. Artistically I prefer the sunny version, but technically I prefer this version, so I'm hoping the judges will be a bit technical! For anyone who's curious (since the voting will be over when you read this), the sunny version can be found on <a href="http://www.deviantart.com/deviation/43121862/">my deviant art page</a>.

Ironically these clouds actually look better than any I've managed to put into a finished full-size scene, because my serious works use assumed_gamma 1 and I just can't make clouds look this good with that more realistic gamma setting! I dunno why! :(