1. First make a new image, 300 x 300 pixels. Press D to revert your colors back to black and white.

2. Go to Filter > Render > Clouds.

3. Now do Filter > Render > Difference Clouds.

4. Go to Filter > Filter Gallery > Stylize > Glowing Edges and use these settings:

5. Now you should have something like this:

6. Duplicate the layer and go to Filter > Noise > Add Noise. Use these settings:

7. Go to your layer palette and add a layer mask (it is the button with a white circle inside a rectangle at the bottom).

8. Go to Filter > Render > Clouds. Part of the white dots should fade now.

9. Create a new layer. Using a white 1px brush, make lines around the canvas like this:

10. Lower the opacity of this lyer to about 20%.

11. Go to Layer > Merge Visible.

12. Now crop a square from the image and resize it to 100 x 100.

13. Sharpen this twice and then duplicate the layer.

14. On the new layer, change the blending mode to overlay.

15. Again, create a layer mask and go to Filter > Render > Clouds.

16. Merge all visible layers and you're done!