Any utils worth installing a GUI on a server for?

[Quartz]

> Have you given any thought to FreeNAS?

I need to do more than what freenas can offer in this case.

> Would you benefit from having multiple xterms open? You know, a couple
> of command lines for your use, a couple for showing the status of the
> machine, etc. All on screen at the same time.

Needing multiple windows isn't my issue. I frequently have multiple ssh 
sessions/terms open to a given machine when I'm messing with it, and if 
for some reason that's not an option I'll just use screen or tmux. 
There's no way I'd install an entire window manager just for that.

I'm mainly looking for anything cool or useful that either can't be run 
through a terminal or otherwise benefits from having some sort of GUI. 
Stuff like GParted or gnome-disk-utility or something (although I don't 
think either of those are awesome enough in themselves to justify 
installing a whole WM). It doesn't have to be gnome/kde/xfce or even X 
based really, I have no restrictions, I'm just curious what's out there.