Basically I want to be able to access different computers remotely (all on Ubuntu 12.04 LTS) that are on the same wireless network. I've gotten this to work for one computer by forwarding port 5900 on my router, so I was thinking I could use forward port 5901 for my second computer. The problem is that I need to change the port that the second computer is listening on for remote desktop sharing (change default 5900 to 5901). Any ideas on how to do this? I am new to Ubuntu btw. Thanks.
Actually you can port-forward the external port 5901 into the internal port 5900 > IP: x and external port 5902 into the internal port 5900 > IP: y, and so on.
It is much simpler because you must only configure one thing -- your router -- and you won't have to remember different TCP ports when you want to reach the various PCs from inside your LAN.
The comment I left above for configuration editor does not work with 12.04. After some more research I found that you can do this with gsettings instead with the following commands:
gsettings set org.gnome.Vino alternative-port 1234 gsettings set org.gnome.Vino use-alternative-port true
where 1234 is the new port you wish to use (typically 5901+).
Remember to setup port forwarding on the wireless router as well. credit goes to: How can I change the port of Remote Desktop?