Zabbix - Track, record, alert and visualize performance and availability of IT resources
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.
Statista - The Statistics Portal for Market Data, Market Research and Market Studies
Prometheus - An open-source systems monitoring and alerting toolkit.
Montecarlito - MonteCarlito is a free Excel-add-in to do Monte-Carlo-simulations.
Grafana - Data visualization & Monitoring with support for Graphite, InfluxDB, Prometheus, Elasticsearch and many more databases