Dns Jumper - DNS Jumper is a portable freeware App which makes changing your DNS settings as easy as clicking a button , it is the world's first IPv6 supported Dns tool
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.
namebench - Provides personalized DNS server recommendations based on your browsing history.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Public DNS Server Tool - Public DNS Server Tool is a small utility for changing the DNS servers in Windows XP, Vista, 7 and...
Better Uptime - We call you when your website goes down