Sometimes I spend time testing things and during the tests I create completely useless stuffs. One of these is: http://myip.mornati.net
It's a simple my ip website that gives you your current public ip adresses, whois information, detailed browser and os information and tools for developers.
For example, there is a page that return your ip adress in plain text (usefull for bash script usage) and another one providing detailes information in json (for more complex script).
There's nothing more... ;)