"(Person) Currently Working On.."
If only you could know when someone else is working on an attached or shared document, like how Wordpress works for example.. Has a clear red bar at the top, "so-and-so is currently editing this document". Then I know to stay clear of it, and everyone is happy!
Anne, do you use Google Drive? At least in this service this is included while you´re editing the document.
In our Notes, you can access previous versions and see who was the last person to edit the document.