I read an article a while ago about using one machine as an X Server, and connecting to this server from *nix and Windows machines, but have lost the magazine Anyone point me to a howto on this?

Basically, what I want to do is have wife start a session on on my machine, from her windows box. She would log in as herself, start X, and use a couple of applications on my machine, but without me seeing it if I am logged into my machine. I know that VNC can do this, but I would like to try it the hard way.