Zabbix - Track, record, alert and visualize performance and availability of IT resources
WikiTribune - Evidence based journalism, from the founder of Wikipedia
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.
Neighborhoods.nyc - Hyper-local alerts targeted by NYC neighborhood
Prometheus - An open-source systems monitoring and alerting toolkit.
Data Dashboard by Wikimedia Foundation - Compiled data of the Worlds busiest public site