The Tips in detail

 "Quick Fog."

Here's a quick way to create fog effects without the need to go to the Environment dialog box:

Create a box in front of the Camera used in the scene. Make sure the Length and Width are big enough to encompass the camera view. Leave the Height at 0. Link the box to the Camera so that it travels with it. Create a new material based on a Gradient Opacity map. Set colors #1 & #3 to black, set color #2 to a medium grey. In the noise section of the gradient, set the Amount to 0.2, the size to 3 and the type to Fractal. You should also animate the Phase of the noise (about 0.5 to 1 unit per 100 frames). If you wish to create something like a sandstorm pushing left to right, animate the U Offset of the Gradient (about 3 to 5 units per 100 frames). Choose a Diffuse color (or map) to colorize your fog. Apply the new material to the box and render your animation.