In this instructable you will learn how to make brushed metal in photoshop. It may also work in The Gimp to but I'm not sure.
Step 1: Create a New Document
I did a 640 x 480 transparent one. But it doesn't matter.
Step 2: Gradient!
Ok new make a Gradient in the document. Use gray. I did semi similar grays so that the difference between the two wouldn't be that much but the gradient adds to the effect.
Step 3: Add Noise.
Go to filter > noise > add noise. Don't set it too high. Oh yeah MAKE SURE that you select Monochromatic or it will be messed up.
Step 4: Motion Blur.
Ok now go to filter > blur > motion blur. Mess around with the distance to get it how you want. I picked 35.
Step 5: Enjoy
Ok now enjoy your brushed metal. If you make Mac software this could come in handy I think.