Getting back on topic... I think that FreeBSD can work great on a desktop (and/or laptop), depending on what you are using it for. If you want games and Flash, then it is obviously not your best choice.
But for me, as a developer, I really only want tcsh; compilers/interpreters for Java, C/C++, and Perl; emacs; NetBeans; pdf and chm viewers; and Firefox; and mplayer. FreeBSD has all of that covered.
The best part is that I can use a simplistic window manager (fvwm) and have my system run extremely fast because I'm not running tons of unwanted processes in the background.
My reason for choosing FreeBSD as a desktop/laptop over a Linux or Windows is that it is really forcing me to learn exactly what is going on inside of my computer, and I have almost absolute control over EVERYTHING!