Step 1. Open a go to File > New (example will be 500x500). Fill your background black. Take your air brush tool and make a 155 diameter circle in the center of your image.
Step 2. Select your smudge tool. I put my settings on size-51, strength- 72%, but you can do whatever you think looks best. Now smudge your image up sorta like this:
Step 3. Now we are getting into the more creative/confusing part. Go to Edit > Transform > Perspective. Using this tool distort your brushing (Be Creative!). Once you have done that go to Edit > Transform > Rotate and place your brushing where you want it on your canvas.
Step 5. Select the layer that you have brushed. Go to Layer > Duplicate Layer. Move the dupliacte layer, and use the perspective, and rotate to this layer as well.

Repeat Step 5 until you have something that you like. Its should end up looking similar to this:
You are done your brushing now all you have to do is apply it to something. This brushing can be used for almost anything (wallpapers, signatures, ect..).
In many cases it is used for abstract 3D renders. I put together a quick example of it in use:
I hope you have learned something!
There are questions regarding how to get from step five to the very contrasting abstract image. Dreamstar7 has stated that the brushing will probably not make the 3D render itself, but the light that comes from it (if you look closely). Hope that clears things up =)
ONLY POST IF YOU HAVE A QUESTION, ANSWER, OR SUGGESTIONS IN ADDITION TO THE TUTORIAL.
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