FFS! Have Pixar been spying on us??

http://www.fubiz.net/2009/06/09/partly-cloudy/

I've no idea how they did this? Rigged Fluids! :S

;)

actually they probably used something like this:

http://www.highend3d.com/maya/tutorials/texturing/3D-Cloud-shader-356.html

cloud shader! This could be the answer - polygon modelled clouds and then given a fluffy animated cloud texture - i think it could be more dense than the example given then a Physical Sun/Sky setup with a pinky/orange light could look good. Could even look at using the RGB lighting Pigeon Impossible technique to get the shadowing right...(i'm thinking out loud)

Will look into this more end of Week2/Week3