cool rock backround

[BlackShadow]

make a new 400x400 document. press d to reset your colors then go to filters>render>clouds then filters>render>diference clouds
then go to image>ajustments>invert
you should have a pic liek tis

then go to filters>render>lighting effects and set the type to onmi, and on the bottom set the texture channel to red and you can change the color of the light to whatever you want. i chose red. now mess with the other settings till ur happy then got o ok. you should have something like this
ur done with the rock part now u can make a kick @$$ backround for a sig. do all the same on a 400x100 document and create a new layer. fill tha layer with the color you want the texture of the rock to be on. now set the opacity of that layer low enough that you can c the textur of the rock.
take some grunge brushes and brush arouwnd a lil bit and you should have a kick @ZZ back round lfor a sig like this

the rock can make a cool explosion effect to when radial blur is affected on it like this