Accessing a machine in my subnet from an external source
 

I'm a newbie on this, but I have researched it some and can't find any help.

I have set up a subnet at my home, and I wanted to be able to access the machines within that subnet from an external source. (VNC for instance). Any help would be appreciated.

You must open the 5900 port on your server to grant vnc access to your local net.
look at this example:
iptables -t nat -A PREROUTING -p tcp --dport 5900 -i eth0 -j DNAT --to 192.168.1.3
where you must replace eth0 with your ethernet card connected to the internet and the 192.168.1.3 with the ip of the internal machine running vnc server.
Good luck!

And what if I wanted to be able to VNC to multiple machines in my subnet, including my server? Is there a way to differentiate between the machines?