awSiteUp will monitor a website at a set interval,and alert you site not respond
Editor: awSiteUp was originally written to fetch an aspx page from DotNetNuke web portals to keep the .Net engine from unloading from memory. However, over time, awSiteUp became a general purpose website monitoring tool.

The Design and functionality have been kept simple. awSiteUp will monitor a website, at a set interval, and alert you when the site does not respond.

awSiteUp can also monitor your Internet facing IP address and alerts you when it changes. Many of us have cable or DSL modems and host services, work remotely, or provide support to users. From time to time, when the cable/DSL modem renews its IP address, it may change and you need to know.

awSiteUp is available in 4 versions.

Demo Edition - Monitor upto 1 website at no cost
Lite Edition - Monitor upto 3 websites
Standard Edition - Monitor upto 15 websites
Enterprise Edition - Monitor upto 100 websites

Features
Runs as a Windows service
Runs on Windows 2000 or higher
Manage awSiteUp via a Web Browser
Self contained web server, does not rely on IIS or apache
Restrict access to the local machine or allow remote access
Each website monitor has its own time Between checks
Each monitor runs on its own Windows thread
Email alerts
Admin and View Only user logins
Allow view only to public or restrict viewing to logged in users
Monitor your Internet facing IP address you can free download awSiteUp 1.1.0 now.