When looking at a list of files, especially in File Open dialogs, if you only have read-access to the folder everything shows as the book icon. Adding one of the small corner markers to the icon to indicate which ones are versions would be very useful.
This would also have a lot of value for Civil 3D workflows when reviewing the .CivilDSProj file's logical set to determine if source drawings are read only because of access control restrictions, or because it is referencing old versions.