Would be cool if one could animate a door swinging by a breeze, or a door opening and closing in a platform that rocks to and fro. Or, if the user could just attach a script to a door or manhole cover/hatch cover on a line (any axis) and have it animate opening and closing.... By extension, fan blades or radars or propellers or anything on a defined axis could rotate or pivot or yaw... irrespective of other objects in motion...