The emblems on icons give hints to the user about files and folders, however these mainly have to be added manually. Examples of more dynamic emblems are the read-only and symbolic link emblems.
I propose that more icon emblems be made which are dynamically allocated. These could even be animated and programmatically updated. Emblems could indicate things like:
* this file is being downloaded (with progress bar)
* this file has an unsaved version open
* this file is being accessed by another user
* this device is unsafe to remove
* this device is safe to remove
* a device's free space (as a progress bar)
* this version controlled folder can be updated
and so on
Applications could even add and update emblems on their own icons. For example:
* email programs could show an unread message count
* news programs could show an unread story count
* messaging programs could show a status icon
* messaging programs could show an unread message counter
* networked applications could show when they're disconnected
* editing programs could show if there are documents to be recovered
* downloading/transferring programs (like BitTorrent) could show a progress bar (or bars)
I would not go as far as allowing interactive elements (like play/next/etc. buttons on a music player) since these would interfere with the icon's main function, plus such things are more like full-blown applets/widgets/screenlets.
A nice benefit of this approach would be the ability to display a large amount of information completely in context (ie. only the information relevant to the displayed icons will be shown)
This could be accomplished using completely animated icons, but the stackable quality of emblems would be more desirable and would require less effort.
Aside from being very useful and incredibly cool, this could offer applications an alternative to abusing the notification area with perpetual icons. Instead they can add functionality to any of their panel launchers. The advantages would be that the icon will be there even if the application is closed, users can move around each icon individually and that the panel already has all of the infrastructure for adding and removing icons, taking that responsibility away from the applications.
PS: Extra special points for doing it in a standardised way for potential cross-platform/desktopness :)
