There are a lot of sites that do exactly the same as this page does, showing your own IP address as we see it here.
Well, to put it bluntly, I truely think all the others stink! They stink because they show you the IP address with a lot of advertising and HTML crap. What human cares about his/her IP address? The only ones are the ones that need the info for some script and a script doesn't care about advertising and HTML. In fact, it only makes things harder, for the script has to filter out the nonsense.
Yep, on this intro page, I do. But if you want to use this script for your own scripts, direct your script to http://b10m.swal.org/cgi-bin/whatsmyip.cgi?just-ip . That link will just show you the IP address, nothing more, nothing less. (Of course you're free to use this page and grep the IP out of the source, if you really like to do that; I even made it a breeze for you to grep ;-)
To make it even easier to get just the IP address, you can also go to http://b10m.swal.org/ip
As usual, you can view the source