Nice
On MS Windows I always saved my icons and start menu items by backing them up weekly with Titan back up. Customized themes can be saved from the Windows settings. I never knew how they would get messed up, but they did.
Anyway this ability is built in to Unity which makes enormous sense. I wonder if you can save a copy of the custom "profile" file and keep it on a USB drive that way it would be a snap in case something got messed up or if you have to reinstall your OS.