AppZero
ServerSuit
RedGate SQL Monitor
Nagios
CULA
Ekran System
Netumo
Squadcast
WebSite-Watcher
Visualping
Distill Web Monitor
Wachete
Update Scanner
UptimeRobot
PageProbe - Automatic Page Monitor
Page Monitor
AppZeroServerSuit - ServerSuit is a browser based program that enables remote Linux administration, monitoring, website hosting, and server setup automation.
Visualping - Visualping is the easiest to use website checker, webpage change monitoring, website change detector and website change alert software of the web. Read more about Visualping.
RedGate SQL Monitor - SQL Monitor helps you and your team find issues – before they become problems
Distill Web Monitor - Distill is a web monitoring tool. It can monitor RSS feeds, a webpage or a part of webpage. Alerts in the form of pop-up, audio or emails can be received.
Nagios - Complete monitoring and alerting for servers, switches, applications, and services
Wachete - Track web page changes and get notified. Free Sign-up. Have all data in one place