Outcome:
1. Fill the canvas with black, and brush with white using a grunge brush. After you have completely filled the whole layer with the grunge brush, go to Image > Adjustments > Auto Contrast, then go to Filter > Sharpen > Sharpen Edges, then finaly go to Edit > Fade Sharpen Edges and do an opacity of 50%. Make a new layer. Repeat Step 1. another 2 times using different grunge brushes.
2. Motion Blur All the layers appart from the bottom layer using these settings. Angle 0 - Distance 15.
3. Set the two top layers to soft light.
4. Make a new layer and fill the canvas with black. Get your best abstract brushes and brush with white. After you have completely filled the whole layer with the abstract brushes, go to Image > Adjustments > Auto Contrast, then go to Filter > Sharpen > Sharpen Edges, then finaly go to Edit > Fade Sharpen Edges and do an opacity of 75%.
5. Put the Abstract Layer below the two grunge layers set on soft light, and set the Abstract Layer to Hard Light.
6. If the Background is too dark, lower the opacity to 75/80%, if its still bad, a lower opacity won't really make it look good, so repeat Steps 5 and 6 using a different abstract brush set.
Optional. If you want depth in the sig, make a new layer above all the layers and click "D" to restore the colors to default, go to Filter > Render > Clouds, and set the layer to overlay, lower the opactiy to an appropiate setting.
7. Put your Render into the sig, resize it and put it to an appropiate position.
8. Duplicate the render and go to Filter > Blur > Motion Blur, with these settings, Angle 0 - Distance 40. Duplicate this layer about 2 more times and move it so it covers the whole sig. Merge the Render Motion Blurred Layers together and duplicate it again. Put one of the layers below all the layers and the other below the render.
9. Set the bottom grunge layer to overlay, and the top motion blurred layer (render) to overlay and move it where appropiate.
10. Make a new layer above all the layers and go to Image > Apply Image > OK. Then go to Filter > Sharpen > Sharpen.
11. Set that layer to overlay and put the opacity to 50%.
Optional. Get the Magic Wand tool and set it to 70/50/10 tolerance. Go down to one of your grunge layers and click randomly while holding shift (not too much though). Make a new layer below the render and fill with a scan line pattern (white). Set the layer to overlay.
12. Do your text and add a border.
