There is an excellent article by Dru Lavigne on about the more subtle parts of X11 configuration. Starting with a short sketch on how to choose the right accelerated drivers for the video card, including the installation of the kernel modules, the author proceeds to explain the more advanced features of X11: nested X servers and distributed multi-head configurations. While nesting (as the name implies) allows you to run several X servers on one screen, distributed multi-head goes the other way by sharing one desktop across multiple machines on the network. Although I won’t use any of the features presented in the article, I nevertheless enjoyed reading and was really surprised how much potential there is in my X11.