Sound notification (Alarm System) would be the best. Sms and Email is good, but might not real time enough.
This sounds interesting. What kind of API can be used to trigger the system you are refering? Is it some URL invocation? Thanks
For example. Nagios is using nagstamon plugin for it's alert/alarm . Reference sites : http://sourceforge.net/projects/nagstamon/
While some other commercial monitoring is using their own alarm system. eg: WhatsupGold "web alarm"
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