This is a wierd question to ask, so let me try to do the best I can... Seeings that Xcode pushes a lot of Object-Oriented design, and OS X is developed around a lot of objects, it seems that one could potentially get a reference to and change-enhance these objects. Something I am interested in doing is changing/enhancing icons. Is there a framework or information somewhere that shows how one can "grab" reference to and modify objects like an icon representation? For instance, making the iTunes icon have a small indicator showing if its playing or not, or adding a tag to a subfolder that shows how many items are in the folder. If someone could point the way, that would be awesome.