It would be awesome to have some analogue of boolean operations in 3D Graphics here (G+) in sharing settings for posts. For example, somebody is added to several Circles like "Friends" and "Work". And here are the examples of what I'm talking about:
1. Choosing 2 or more Circles and the "Intersection" option:
The post may be viewed only by the people, who are added to all of the selected Circles, but not bye the ones, who is added to only one of these Circles.
2. Choosing one or more Circles and the "Subtraction" option with selecting the Circles I want to subtract:
The post may be viewed by the people from the selected Circles, excluding the ones, who are also in the subtracted Circles. For example:
share with: Friends; Subtract: Work => Nobody of my co-workers will see the post, even the friends, who work with me.
3. The third option could be some antipode of the Intersection operation: the post may be viewed by the people from several Circles, excluding the ones, that are added to several of them, but this seems to be meaningless to me :)