X11
On your install disks as an optional install is a program called X11. It lets you remotely access unix programs and run their full GUI on your Mac if the program uses the X11 windowing system. This is also available for download from Apple if you can't find it on your disk.
Basically, after you install it and open it you have a command line almost exactly like a unix terminal. ssh with a -x or -y flag into the remote unix machine and when you open a program from that command line its windows should pop up on your Mac.