Sometimes unintended rendering outcomes are worth saving. Not only pictures, but more importantly also the settings.
I happen to like the color interactions of the attached picture very much. I was intending to use the picture as a possible painting subject matter. However, by the time I had created another torus-knot with much higher mesh density. I had lost the settings of the original file. I have been trying to duplicate the Vray settings ever since without success so far.
in 1.48.66, whenever you render, an xml file is generated. The xml file contains all settings, materials, geometry, lights, etc. This file gets replaced every time you render. So if you wanted to, you could render, and then copy the xml file somewhere for reference later, then render again, copy that somewhere, etc.
XP: “C:\Documents and Settings\All Users\Application Data\ASGVIS\VfS\current_skp.xml”
Vista/Win7: “C:\ProgramData\ASGVIS\VfS\current_skp.xml”
OS X: “/tmp/current_skp.xml”
We don’t normally mention that this file exists, because it’s not all that useful, and it can be rather large/complicated. I just thought I’d mention it, because someone might be able to do something useful with it.