Okay, I guess I will be a nice guy and share.. It's actually quite simple.
Step 1.
Go get
wget for Win32
Step 2.
Make a Batch File that looks like this:
@echo off
REM This will first go get your IP
wget -q http://dynupdate.no-ip.com/ip.php
REM Then this command shows it to you!
type ip.php
REM Then this command removes the rouge file.
del ip.php
I named mine getip.bat.
Step 3.
Put those two files in a place that is in your PATH.
(If you do not know this start another thread. And personaly I think this whole thing should be in the support forum but okay.)
Step 4.
Have Fun running your new batch file that will output your external IP!
There is no native command to get the information that you want. So this is the easiest way I think you can get it from a COMMAND PROMPT. There is no DOS!