WhoisAPI - WhoisAPI is the premier provider of freshly parsed whois data for domain names and IP addresses...
IP-Toolbox.com - IP-Toolbox.com is the best site for quick and easy viewing of your public IP address and other related information.
WhoAPI - WhoAPI is an API service for mass requests of domain information like domain registration availability and structured whois data in JSON.
GRC Port Scan - GRC Internet Security Port Scanner. Tests for open ports on your external IP address.
WhoisThisDomain - Domain name lookup tool that allows you to get information about domain registration from WHOIS server.
TrueIP - TrueIP is a small program that runs in the system tray, monitoring your IP address(es).