The Visual Studio editor tracks changed lines and displays them on the selection margin: yellow – changes since the last save, green – saved changes since file opening, orange – reversed changes (undo) after a save operation. I think it can be useful to indicate changed files in the tab title as well. An orange bar instead of the default asterisk for files changed since the last save (orange looks better than yellow in the tab title), plus a green bar for saved files:

Changed file indicators in tab titles
I’ve implemented it as the TrackEd add-in for Tabs Studio. These indicators should visually separate tabs you edited and other tabs used only for viewing. Give it a try and share your experience!
Download link: TrackEd v1.0. (Don’t forget to unblock the TrackEd.dll file after downloading from file properties.)
P.S. To clear tracking changes and the title indicator for a saved file, you can use this command for Visual Commander. (It works independently of Tabs Studio.)