And if you wanna get really crazy, you could try ControllerMate. You can play with the functionality of the keys, and control the LED diodes on your keyboard. I have mac set up to deactivate caps lock, and CM to have its light turn on when I'm pressing Shift. Further, I have it set so after 1.5 seconds of holding Shift or Spacebar, the three LEDs will blink in succession over and over.
Besides that, I've changed where my volume and brightness controls are, as well as PrintScreen.
I feel like a program like ControllerMate is essential for customizing key controls.