This Universal Material Converter is an enhanced version of the old AMC script. It convert materials between renderengines. It converts from Autodesk Materials and also converts textures as much as possible when needed.
Currently supported renderengines are: MentalRay, V-Ray, iRay, Corona, Scanline.
Coming up: Maxwellrender, Octane
You will need at least have a demo version of the renderengines installed if you want to be able to support conversions.
While for example converting a V-Ray material to Corona, it will also convert bitmaps to Corona-bitmaps and VRayDirtmap to CoronaAO.