Zabbix - Track, record, alert and visualize performance and availability of IT resources
ProtonVPN - ProtonVPN is a security focused FREE VPN service, developed by CERN and MIT scientists. Use the web anonymously, unblock websites & encrypt your connection.
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.
OpenVPN - OpenVPN - The Open Source VPN
Prometheus - An open-source systems monitoring and alerting toolkit.
TunnelBear - Really simple VPN to browse the web privately & anonymously.