Xming is indeed a wonderful tool. IMHO.
It is available on sourceforge, project ID is xming
Xming is a small download and is free. It provides a native X server for Windows (even Vista ;)), meaning your PC now becomes a proper X terminal.
For a while now I’ve been looking for a tool to administer my Linux servers. SSH is nice and secure, but text-only. VNC is graphical but not terribly secure, and depending on your distribution may require a reasonable amount of server setup. Or there’s Telnet, rlogin, browser based admin tools…
I’m not one of those masochists who think that Linux servers must be administered by command line, if a graphical interface exists and works why not? But I like the fact that ssh is nice and secure, and is pre-installed and configured.
Using Xming you basically make your Windows PC fully X-capable. X-windows is client/server based anyway, so why reinvent the wheel and use, say, VNC when all the server-side stuff you need is already there? Plus, just about every UNIX/Linux/BSD/Sun/OS X device is X compliant. So using an X client means you can connect to them all.
Xming can work over an SSH tunnel, remote over the internet, via XDCMP or just about any other X methodology, so is nice and flexible. I’m typing this on a Vista laptop connected wirelessly over a mixed network to a Fedora Core 7 server which is running Firefox to TPR. Performance and screen quality are excellent, no lag, no corruption. Easy bloody peasy.
If you have a Linux box, take a look. You won’t regret it.