`nvidia-settings` is a commandline utility to control graphic card configuration. It's used to set things like SyncToVBlank, FSAA level, Vibrance, multihead positioning, and even GPU and Fan speed, since you can also query temperature.
Hacking the original nvidia drivers is pretty much impossible, they are closed source after all :)
One of the first things I've implmeented when I learned programming was mapping ACPI events of multimedia buttons to various calls to XMMS. Having something physical to relate to while coding is a big help for me, and makes a lot of sense. I assume that's one of the reasons a lot of people get arduino, rPi, beagleboard, etc... If it moves or interacts with the environment, it's easier to wrap your head around it, and more rewarding when you get it to behave as you want it to.