This tutorial was originally posted on my site here http://theironknuckle.com/tutorials/gimp-b...l-tutorial.html
This tutorial will show you how to create a grunge/brushed metal background for images/signatures using GIMP! Start With a 500 x 500 white Canvas.
1)
Filters>Render>Clouds>Solid Noise
5.0 for both X and Y
Tick Turbluent
2)
Fliter>Blur>Pixelize
choose 10 by 10
3)
Filter>Blur>Motion Blur
Choose Zoom and 50 for Parameters
Filters->Disorts->Emboss. Values as below.
4)
Filters->Edge-Dectect->Edge. Algorithm=Prewitt, Amount=9, Wrap
5)
Fliter>Blur>Motion Blur (using the following)
6)
Layer>Duplicate Layer
Layer>Transform>Flip Horizontally
Layer>Transform>Flip Vertially
7)
Set the Top Layer's Opacity to %50
Image>Flatten Image
8 )
Layer->Colors->Colorize (choose whatever you want)
Here is What I got!
this is what i got 
