These free tools will periodically check server response times and notify you if your web server is slow or unavailable.
NetMechanic ServerCheck
http://netmechanic.com/server_check/site_monitoring.htm
This tool will watch your server for the next 8 hours and send you email alerts.
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InternetSeer Web Site Monitoring Service
http://www.internetseer.com/activate/index.xtp?option=1
FREE Web Site Monitoring. InternetSeer remotely monitors your Web site 24 hours a day, 7 days a week, and alerts you by email or pager email when your Web site goes down
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Build a C# Web Site Monitor Service
with Email and MSN Messenger Notification
By Peter A. Bromberg, Ph.D.
http://www.eggheadcafe.com/articles/20040516.asp
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Right Web Monitor (v. 1.41)
Right Web Monitor is a handy tool that lets you automatically check your favorite Internet resources and detect changes in their content. With Right Web Monitor you can keep track of any kind of resource, including web pages, applications, images, etc. If the monitored resource changes, the program will immediately notify you. You can also choose to automatically download the modified files.
http://www.right-soft.com/webmon/
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