powermated is a program for controlling X applications and command line programs, and for monitoring various aspects of your computer with the Griffin PowerMate USB dial. It can update the PowerMate's LED based on different system monitors (such as CPU usage, XMMS/BMP sound output, and system mixer volume). It also has XOSD support for nifty on screen status displays.
Gizmo Daemon is a program for controlling your computer based on events from input devices. It has built-in support for all Linux input devices, including keyboards with special keys, joysticks, remotes, dials, and more. It lets you control applications, launch programs, change the system volume, switch desktops, and directly control Amarok. It can visualize system events (such as Amarok sound output, CPU usage, etc.) on capable devices (keyboards with LEDs, Griffin PowerMate, etc.). It also features support for LIRC and RF based remote controls, allowing it to have per-application key mappings and configurable sensitivity settings.
This is a discussion of X window managers, not how they relate to current desktop systems such as KDE, and GNOME. I personally use Enlightenment, because not only am I an eye candy junky, but I dig functionality too. I like quick access to virtual desktops via keyboard, and the ability to perform massive customizations. I like the availability of many themes, and a strong loyal community style user base.
However, I think Ion (http://modeemi.cs.tut.fi/~tuomov/ion/) is a particularly interesting WM, with it not using windows at all, rather it splits up the screen space into many frames.
I wish the author had touched on all of the pro's, and con's of most of the major WM's, and then talked about some of the more unique one's out there.
To me, this seems like an article that got started but never finished.