Anturis - Anturis offers hosted server monitoring software (SaaS) for both Windows and Linux.
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.
Zohno Z-Term - The Easy-to-Use Active Directory User Termination Tool
AppDynamics - Get real-time insight from your apps using Application Performance Management—how they’re being used, how they’re performing, where they need help.
NIXStats - SaaS monitoring tool for window/linux servers and websites. Think up-time robot but with more features.
Zabbix - Track, record, alert and visualize performance and availability of IT resources