Got too many unused project references in your face? Clean them up with the aptly named 'Remove Unused References' extension!
Just right-click on a project (or solution) and choose 'Remove Unused References' from the menu and this extension will go to work while you wait (*). After it's done you can almost smell that lemon scent.
(*) in order to ensure that only really unused references are removed, the selected project(s)/solution will need to be built in all project configurations (debug/release, x86/x64, etc..) now's a good time to check the underside of your mouse for lint, just to enhance that fresh, clean feeling!