When you need to know where your current drawing is stored.
The DWGPREFIX Command
Autodesk's Jerry Bartels reminds us of the DWGPREFIX command.
The command displays the storage location of the current drawing in both
the Command line and a tooltip.
From the Jerry's YouTube Channel.
and the Civil Imersion blog.
If the drawing tabs are turned on in your workspace(the default),
then a simple mouseover of the drawing tab will get you the same visible information with less effort.
The Recent file list also display's the full path.
But DWGPREFIX gets you the result in Command Line text form that you can copy. That alone can be very useful.