WebGazer - Monitor your website's availability with WebGazer, review its performance and get instant notifications when your website goes down. No installation required and free plan available.

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.

Hyperping - Cheap uptime and performance monitoring with detailed reporting and flexible alerting

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.

Oh Dear! - Website monitoring, without the hassle

Wachete - Track web page changes and get notified. Free Sign-up. Have all data in one place