Kuro5hin takes a look at tiling window managers, which organize windows in non overlapping ways. It's an interesting system of management. I can find no real use for it myself under most circumstances, especially on my large work monitor. There, I do employ tiling-esque techniques, and I imagine a lot of others do without realizing it - at least, in the Mac world which doesn't suffer from the MDI dichotomy that Windows has, where Word tends to open up a new Big System Window for every document but Excel tends to keep spreadsheets managed inside the big Excel window. Access and many other programs suffer from this too. On the Mac, a window is a window is a window, and organization is pretty easy.
Apple has made working with windows even better in Mac OS X. On top of the Exposé window switching system, which can thumbnail all visible windows rapidly for context switching, a favorite little feature of mine has been the near-omnipresent adoption of the "Hide Others" command and key shortcut, "Option-Command-H". A similar feature in Windows is the "Minimize All" feature in the context menu of the Windows Taskbar. But unlike 'Minimize All', 'Hide Others' keeps your current application and window and cursor on top and in the same position. It's a great key chord to hit when there are too many distractions on the screen, and it's one of the few major Mac OS X actions without animations - other applications just hide, and you keep on doing what you're doing with hardly a second thought - just the quiet peace of a clean screen. Even minimized windows of other applications disappear from the dock (there is a brief animation for this, but never distracting). I've found it more effective than any "virtual desktop" system, which I've always found to be worse than the usual window clutter, as I have a hard time keeping up with all my desktops. And, for some reason, the context switching between desktops has always been jarring for me. Having a single desktop, especially now with Expose, keeps me relatively free of the "where did I put that logtail window?" games.