Author: Ryan Muder,
URL: http://www.gfxgamers.net

Make a new document, (I used 500x500px)

Then, Filter>render>clouds
Filter>render>differance clouds

You should have this:

Now, go to filter>pixelate>Mezzotint; Type=long strokes
Filter>blur>radial blur. Amount 100; Method: Zoom; Quality:Best
Press ctr+f
Again, press ctr+f

You should have this:

Duplicate the layer
Now, do Filter>distort>Wave with default settings, randomize until you get a good result

Now, set the layer mode to Lighten, and merge.
Duplicate the layer

Press ctr+t, right click, and flip it vertically
Set the layer mode to lighten, and merge.
Duplicate that layer
press ctr+t, right click, and flip it horizontally
set that layer mode to lighten, and merge.

Now, just add a good color. (ctr + B)