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.
LTSP - The Linux Terminal Server Project adds thin-client support to Linux servers.
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.
Thinstation - Thinstation is a basic and small, yet very powerful, open source thin client operating system...
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Nakama - Nakama is an open-source distributed social and realtime server for games and apps.