Now you just don't want plain skies all the time right? Well the clouds feature is just wicked sick. You can either create 2D or 3D clouds.

The 2D clouds render extremely fast, and they look good when you're looking up at them. The slight downside is if you want to do a camera fly through of the clouds, this really won't work because all the 2D clouds are but a 2D plane really. So if the camera goes through the layer it won't look real because it's really thin.

3D clouds on the other hand will do this kind of thing perfectly because they're true volumetric clouds. Also there are two different cloud types, Stratus and Cirrus. Stratus clouds are the ones that you see almost everyday. They look big and puffy and they usually are lower to the ground. Cirrus clouds are the ones that are really high in the sky and are scattered around.

DS has this nifty thing called the preview window when working with sky and clouds. It lets you, in near real-time, manipulate the clouds and get the positioning right before you do your actual render. The left window is what the output will be of your scene, and the right is for the initial cloud shape.
With this you can click and drag around and get different shapes. While you do this the left window will automatically update to what you just adjusted.
There's also another way to see cloud layers. You can localize them so they don't cover the whole sky and constrain them within a certain radius. This is really useful if you just want a spherical shaped cloud in the sky. I just love how simple it is to create any kind of sky environment.

Alrighty, now remember back when I said the panorama feature was really cool? You can specify any render size for it to create the panorama image. So, it's really useful if you're doing a still shot with no animation. Just map it on to a sky dome and your set! Below is a sample of what it looks like when rendered out.