Scratched & Dusty Metallic Paint Shader version 1.0, for mental ray maya 2009.
For best results, use a High Dynamic Range image as an environment texture. You can find great HDRI-maps at Paul Debevec's website www.debevec.org
The shader is 100% procedural which means that it uses only 3d-textures and that there is no need to consider UV-mapping.
The shader uses mia_material_x materials, they are backwards compatible with maya 2008 (mental ray 3.6). To open the file in maya 2008 check "Ignore Version" in options when you open the file.
The shader is build of three components: scratched lacquer, clearcoat and dust. Parameters can easily be tweaked (amount of dust / scratches, color, reflection etc).