Find out your IP in Linux

Finding out your PC’s IP in Linux is a simple matter of typing ifconfig in a Terminal shell. But what if you’re behind a router? Thanks to a simple shell script, you can display your IP in the command line by simply invoking the whatismyip command.
Do this:

cd /usr/bin
sudo nano whatismyip

In the new file paste this:

#!/bin/bash
curl -s myip.dk |grep ‘”Box”‘ | egrep -o ‘[0-9.]+’

Close and save the file then make it executable:

sudo chmod +x /usr/bin/whatismyip

Now every thime you type whatismyip the IP assigned to you by your ISP will be printed in the Terminal window.
Original idea here.