Further to the question about remote X on Fedora.
I was able to get my remote X working via an SSH tunnel simply by logging in with ssh as follows:
ssh -X <userid>@fedoramachine.com
Once logged in you can invoke any X command and it just works.
The -X option sets up everything for you automatically and note that "X11Forwarding yes" is still the FC3 default in /etc/ssh/sshd_config.
Perhaps everyone but me knew about this already?