About a week ago, I was geeking out over E17 on my newly installed Ubuntu installation. Then I found a window manager which was even more slick, though very light in the eye candy department: wmii, which apparently stands for 'Window Manager Improved II'.
It's an unusual in that it's a dynamic window manager, which means that it arranges your windows for you, rather than making you drag and resize them to make the best use of the space. When you open a window, it fills the screen. If you open another, it is tiled below the existing window. You can also make a new column, which splits the screen vertically and places the second window next to the first. There is also a 'stacking' mode, where the unfocussed windows have just their title bar visible and you can flip through them with a keyboard shortcut, a 'maximum' mode where all windows are maximized, and a 'floating' layer for applications like music players which have non-standard windows.
Instead of the familiar Linux workspace metaphor, there are tags, which allow you to group your windows into views (so you can have browser windows in one view, terminals in another, etc.).