A skybox is one of the most typical ways to create a sky for a game. A sky texture is mapped onto a large sphere or box, which then surrounds the game environment to provide the illusion of a sky and distant background. Skyboxes can, however, be a pain to make, requiring a lot of touchy manipulation and set up. With this tutorial, you'll learn how to use Blender to make fairly realistic skyboxes quickly and easily.
The tutorial includes a .blend file and walks the user through the basics of setting up the textures on a sphere, which is then rendered into six panels, allowing the texture to be applied seamlessly to a box. This creates the illusion of a perfect sky while only using six faces, a real performance saver. Thanks go to Ken Beyer for this useful resource.