I took this photo with the 5D MK III's "in camera HDR option". I have to say, I'm quite pleased. I've never been a huge fan of HDR: many images I see (including some of my own attempts) look over processed and artificial.
But here, I think the camera has done a very nice job enhancing the scene, while maintaining a natural look.
This has absolutely NO post processing, and neither does the comparison .jpg image I'm posting. Both are straight from camera.
Both are hand held too ... so the camera auto aligned the images to create this (that's why you see a bit of the edges cut off in comparison to the .jpg).
If I were to do any post processing to this scene, I think I might try to brighten up the foreground just a bit more and desaturate it, to take that slight bluish tint out of the snow. That would be about it, I think the sky is pretty much perfect as is.