it's much more energy efficient than my desktop and it doesn't make any noise. plus i can carry it around with me (at least in wireless range)
there's a set of tools at
http://www.pocketworkstation.com i used to set everything up. basically, the zaurus is an arm chipset, and openzaurus is the distribution you can install over the factory-installed one. (the factory one is linux too, but it's an old gadget and openzaurus is significantly more up to date)
pocketworkstation is a debian tarball you unzip into a directory which is its own operating system, living entirely in the larger openzaurus linux distribution through the magic of chroot. (chroot changes directory to something and makes it root, and has measures to somewhat prevent people from accessing other directories on the system if they're smart).
of course, when i say server, i'm really just talking about a desktop running linux for messing around type things, having gaim and thunderbird open also, and possibly xmms if i feel like it. it's a bit slow when doing things over vnc but for a total price of $230 i'm not complaining. ($130 zaurus pda + $30 wireless card + $70 1gb securedigital card)
