Tracking changes in IP address might be just important for you if you connect to any remote machine remotely or when if you have a team in place who access a remote machine more often than you cannot just afford to get disconnected any time.
Email WAN IP address is a small utility with lot of turbo charge to update you when the IP changes. The best part is it gives you more option than just email. You can Text to a number and also get DM to a twitter address
Very good looking GUI, and very usable program.