MacOSXHints: Set system and network prefs from the Terminal. There have always been command line tools for setting prefs in Mac OS X Server; this article shows you how to get access to the same tools by installing the free Apple Remote Desktop client, and walks you through a few sample uses.
This always drove me nuts on Windows XP. If you’re going to have a command line in a system at all, it would be nice if you could do some useful things with it—especially on remote machines.