1. A simple 50% grey with difference clouds on a transparent layer 2. Select a small section, full width, from the top and cut 3. Paste into new layer and drag down, holding the shift key, to the bottom of the base texture 4. Erase with a soft brush, don't go too near the bottom edge, until happy with the effect. 5. Merge down, and select a small section, full depth from the left and cut 6. Paste into a new layer and drag across, repeat the erase and merge down 7. A bit rough but you get the idea The only drawback is that the final image is smaller than the original, and the more work you put in to the erasing the better. Works for any image though...

buddyh, always amazed at what I forget, and always amazed at how many ways there are of doing things in Photoshop. Hope the guys below read your suggestion:)