A simple vbs script that accesses a http page to get the public IP-address and writes this and the current date and time to a text file. What site is used and the name of the text file are easily updated be chaning variables at the top of the script.
The script may for example be started every day at a certain time using Windows Task Sceduler.
Can among other things be used to check or double check if your internet service provider gives you a static IP address.