Images: abs_wave, metal, sky, rust, sand, wood, water, tiles, stones, lava
Origin: 3D Studio Max 6.0
http://www.autodesk.com

Images: gradients, noise
Origin: Jerzy Stachera (c)

Images: skin (Dawn), plates (Gas Station), grass (Timbury)
Origin: NVidia Demos
http://www.nzone.com/object/nzone_downloads_nvidia.html