Hyperping - Cheap uptime and performance monitoring with detailed reporting and flexible alerting
Platypus - Realtime server monitoring and reporting
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Healthy Servers - Making server monitoring easy
Nagios - Complete monitoring and alerting for servers, switches, applications, and services
PING - PING (Partimage Is Not Ghost) is a free software Linux-based live CD ISO built upon the partimage...