curl -s checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//'

curl ipinfo.io/ip

$ wget -qO- http://ipecho.net/plain ; echo

$ curl ipecho.net/plain

$ curl ipecho.net/plain ; echo

$ dig +short myip.opendns.com @resolver1.opendns.com

111.222.333.444

$ LANG=c ifconfig <interface_name> | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}'

$ LANG=c ifconfig ppp0 | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}'
111.222.333.444

$ LANG=c ifconfig | grep -B1 "inet addr" |awk '{ if ( $1 == "inet" ) { print $2 } else if ( $2 == "Link" ) { printf "%s:" ,$1 } }' |awk -F: '{ print $1 ": " $3 }'

$ LANG=c ifconfig | grep -B1 "inet addr" |awk '{ if ( $1 == "inet" ) { print $2 } else if ( $2 == "Link" ) { printf "%s:" ,$1 } }' |awk -F: '{ print $1 ": " $3 }'
lo: 127.0.0.1
ppp0: 111.222.333.444

curl ifconfig.me

curl icanhazip.com

curl ipecho.net

curl icanhazip.com

curl ipv4.icanhazip.com

wget -qO- icanhazip.com

curl ident.me
curl v4.ident.me
curl v6.ident.me

$ dig +short myip.opendns.com @resolver1.opendns.com

wget -O - -q icanhazip.com

$ telnet ipecho.net 80
Trying 146.255.36.1...
Connected to ipecho.net.
Escape character is '^]'.
GET /plain HTTP/1.1
HOST: ipecho.net
BROWSER: web-kit

HTTP/1.1 200 OK
Date: Tue, 02 Jul 2013 07:11:42 GMT
Server: Apache
Expires: Mon, 26 Jul 1997 05:00:00 GMT
Cache-Control: no-cache
Pragma: no-cache
Vary: Accept-Encoding
Transfer-Encoding: chunked
Content-Type: text/html

f
111.222.333.444
0

curl http://checkip.amazonaws.com

123.123.123.123

curl ipecho.net/plain

telnet myip.gelma.net

Your IPv4: xxx.xxx.xxx.xxx
Your IPv6: ::ffff:xxxx:xxxx

$stunclient stun.services.mozilla.com
Binding test: success
Local address: A.B.C.D:42541
Mapped address: W.X.Y.Z:42541

stunclient stun.services.mozilla.com |
    sed -n -e "s/^Mapped address: (.*):.*$/1/p"

$echo -en 'x00x01x00x08xc0x0cxeex42x7cx20x25xa3x3fx0fxa1x7fxfdx7fx00x00x00x03x00x04x00x00x00x00' |
    nc -u -w 2 stun.services.mozilla.com 3478 |
    dd bs=1 count=4 skip=28 2>/dev/null |
    hexdump -e '1/1 "%u."' |
    sed 's/.$/n/'

$ exec 3<> /dev/tcp/icanhazip.com/80 && # open connection
  echo 'GET /' >&3 &&                   # send http 0.9 request
  read -u 3 && echo $REPLY &&           # read response
  exec 3>&-                             # close fd

curl ipv4.ipogre.com

curl ipv6.ipogre.com

import urllib, urllib2, cookielib
import re
from subprocess import check_output as co

cookie_jar = cookielib.CookieJar()
opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookie_jar))
urllib2.install_opener(opener)

def get(url, values=None):
  data = None
  if values: data = urllib.urlencode(values)
  req = urllib2.Request(url, data)
  rsp = urllib2.urlopen(req)
  return rsp.read()

router = co(['ip', '-o', 'ro', 'list', '0.0.0.0/0']).split()[2]
url = "http://" + router

get(url+"/index.asp")
get(url+"/LoginCheck", dict(checkEn='0', Username='admin', Password='admin'))
page = get(url+"/system_status.asp")

for line in page.split("n"):
  if line.startswith("wanIP = "):
    print line.split('"')[1]
    exit(1)

ifconfig

ifconfig | grep inet

ip addr show

hostname -I

wget http://smart-ip.net/myip -O - -q ; echo

curl http://smart-ip.net/myip

lynx bot.whatismyipaddress.com

ip addr show

curl "http://fritz.box:49000/igdupnp/control/WANIPConn1" -H "Content-Type: text/xml; charset="utf-8"" -H "SoapAction:urn:schemas-upnp-org:service:WANIPConnection:1#GetExternalIPAddress" -d "<?xml version='1.0' encoding='utf-8'?> <s:Envelope s:encodingStyle='http://schemas.xmlsoap.org/soap/encoding/' xmlns:s='http://schemas.xmlsoap.org/soap/envelope/'> <s:Body> <u:GetExternalIPAddress xmlns:u='urn:schemas-upnp-org:service:WANIPConnection:1' /> </s:Body> </s:Envelope>" -s

grep -Eo '<[[:digit:]]{1,3}(.[[:digit:]]{1,3}){3}>'

curl -s 192.168.1.1 | grep "ipinfo" | awk -v FS="(IP: |</span)" '{print $2}'

curl -s -u your_ddwrt_username:your_ddwrt_password http://192.168.1.1 | grep "ipinfo" | awk -v FS="(IP: |</span)" '{print $2}'

echo $(ip route get 8.8.8.8 | awk '{print $NF; exit}')

sudo traceroute -I google.com

user@user-PC ~ $ sudo traceroute -I google.com
traceroute to google.com (173.194.46.104), 30 hops max, 60 byte packets
 1  25.0.8.1 (25.0.8.1)  230.739 ms  231.416 ms  237.819 ms
 2  199.21.149.1 (199.21.149.1)  249.136 ms  250.754 ms  253.994 ms**

sudo traceroute -I google.com | awk -F '[ ]' '{ if ( $2 ="2" ) { print $5 } }'

(199.21.149.1)