Another simple way to get external IP or use:

wget -qO- http://ipecho.net/plain

looks at html for "ip" (it's a CSS class), then a little of cut and egrep to get IPv4 address.

I use this oneliner into conky.

Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way.

This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1).

This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

Short list of all ip.

Shows even the newly supported multiple ip address on the same interface (see eth1).

For ipv6 use -6

Asks Google what your current IP address is. Bonus: Remove "@ns1.google.com" and you will instead get the IP address of your DNS server.

That's the easiest way to do it. -I (or capital i) display all network addresses of a host

gives u each configured IP in a seperate line.

Does a ping scan on the local subnet and returns the IPs that are up

Gets all kind of info, ifconfig.me rocks ...

for just the ip addess you can use ifconfig.me or ifconfig.me/ip

Your IP address is 0.0.0.0

Shortest url to a external IP-service, 10 characters.

Gets the IP and sticks it into the middle-mouse-click buffer

Grabs your external public IP.

This command shows a sorted list of the IP addresses from which there have been authentication errors via SSH (possible script kiddies trying to gain access to your server), it eliminates duplicates so it's easier to read, but you can remove the "uniq" command at the end, or even do a "uniq -c" to have a count of how many times each IP address shows in the log (the path to the log may vary from system to system)

This is just a "cut" addicted variant of the previous unixmonkey24730 command...