A crafty MacBook owner has gone through the tedious act of switching his MacBook's QWERTY keyboard for the Dvorak layout. The Dvorak layout (named after Dr. August Dvorak, not that Dvorak) was created to let people type faster. It places the most common used letters in the middle row and the least used keys on the bottom row. Getting your Mac to recognize the Dvorak layout is a simple matter of tweaking the input settings in your system preferences and from the looks of the photo gallery, getting your keyboard set up isn't that much harder.
Michael: it doesn't quite work like that, at least for me.
I bought a Kinesis-ergo keyboard because my wrists hurt. They lay out the keys in vertical rows because that's how our fingers are designed to move (no diagonals=less stress). It kept throwing me, especially the N and M placement.
So I decided to learn the dvorak layout. One of the changes I decided to make was to get myself properly retrained by typing slowly and deliberately rather than using my "pinky of death" to delete my mistakes really quickly.
The end result is that I make many fewer mistakes when I type, there is much less stress, and from what I can tell my output is about the same. Either way I tend to be limited more by my brain than my fingers.
It is also my experience that switching between layouts is not difficult because I know how to type qwerty so well. I consider myself bilingual.