1)   A1Monitor Network Monitor TCP or Web 6.1.70
Monitor multiple web or TCP servers (http, https, ftp, pop3 etc.) Receive email notification by email or pager if any can't be reached a number of times in a row

 2)   WebWatchBot 3.0
Monitoring & Analysis Software for Web Sites & IP Devices. Maximize availability through accurate, in-depth monitoring & alerting functionality. Analyze historical data for trends & visualize current state with real-time charting & graphs.

 3)   WebWatchBot Website Monitoring Software 5.1.6
Constant monitoring is critical to ensuring your website and web-based applications are error free and performing with acceptable response times. WebWatchBot 5.0 is the leading software solution for performance monitoring and problem notification.