TrueIP - TrueIP is a small program that runs in the system tray, monitoring your IP address(es).
Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
My Public IP - My Public IP is a utility to let you know through which internet IP the world see you.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
IP-Toolbox.com - IP-Toolbox.com is the best site for quick and easy viewing of your public IP address and other related information.
Better Uptime - We call you when your website goes down