Here’s a set of free patterns for photoshop and gimp, which were extras from the last set of layer styles. You can switch colors with the patterns in modification of the previous styles set or use them as backgrounds. They also make quick and easy seamless textures for layering.
By the way…
If you don’t know how to install/use patterns in gimp, you can check out this Gimp Pattern Fill Tutorial
.PAT file for photoshop click here
Seamless tiles for gimp click here