Binary package hint: gnome-screensaver
The gnome-screensaver has a list called 'Screensaver theme' which contains a shortlist with 'Black screen' and 'Random', a separator bar and then all installed screensavers.
At the moment the list has become so long that it takes a long time to find, that particular screen saver you would like to see or show to others, that it is desirable to allow the user to add and remove screensavers to the shortlist. This can be achieved by offering the following functionality.
With a mouse right click on a screensaver in the long list, a menu should pop up with the action 'Add to shortlist' and when clicked that particular screensaver will also be listed in the short list above the separator bar. With a mouse right click on a screensaver in the short list (i.e. not on 'Black screen' and 'Random'), a menu should pop up with the actions 'Remove from shortlist' and when clicked that particular screensaver will have to be removed from the short list.
Implementing this feature will allow users to more actively switch between favorite screensavers enabling them to quickly demonstrate what are, according to them, the most awesome screensavers Linux has to offer. And in turn making a nice showcase for GNU/Linux.
While you are at it ;) please extend the entire list of screensavers from:
Blank screen
Random
Separator
Items in long list
...
into:
Blank screen
Random long list
Random shortlist
Separator
Items in shortlist
...
Separator
Items in long list
...