Ubuntu VNC glory
I needed to have a friend pull my vnc client the other day, and in UltraVNC in Windows, you can just set the client on 'listen mode'. I didn't know how to do this in Linux, but the answer was easy:
vncviewer -listen 5500
And the server
The server was just as easy to set up:
x11vnc -forever -usepw -httpdir /usr/share/vnc-java/ -httpport 5800 -listen 192.168.1.103
Make sure and -usepw or you'll open your machine up to a world of trouble :)
Aaron