The overlapping window manager model has been dominant a long time. New innovations like Apple's Expose are evolving the paradigm. Tiled layouts are quite common within a single application. Why hasn't it caught on for window managers, or window manager users? Isn't it time for applications to share the desktop more nicely? Alternatives have been well studied and look promising from a theoretical efficiency standpoint. Available today are Ion for Unix and now WindowSizer for the Microsoft crowd. With bigger monitors, higher resolution displays and multimon systems the overlapping is only going to get messier.