My friend and coworker Guillermo Melantoni wrote a great blog post in June on modifying your AutoCAD UI colors. I have now saved a profile and workspace with these great colors. In Guillermo's post the settings to change in the Options dialog are listed and only take a minute to setup and then save a profile for using in the future.
The colors are really nice when working in 3D as I was today in this 3D metal salmon sculpture.
So what do you think of the blue themed 3D UI colors?