Thought I'd recommend this application that makes it easier to use all of your screen real estate and to quickly organise multiple windows for viewing at the same time. It's got the element of what I liked when trying xmonad on Linux, but without being such a departure. Having one of the partitions be narrower is nice for having "auxiliary" apps alongside the main one you are using.
http://www.irradiatedsoftware.com/sizeup/
Screencast: http://www.irradiatedsoftware.com/sizeup/assets/SizeUp.flv
http://www.irradiatedsoftware.com/sizeup/
Screencast: http://www.irradiatedsoftware.com/sizeup/assets/SizeUp.flv