Fping (open source) - fping is a program to send ICMP echo probes to network hosts, similar to ping, but much better performing when pinging multiple hosts.
ServerSuit - ServerSuit is a browser based program that enables remote Linux administration, monitoring, website hosting, and server setup automation.
Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.
RedGate SQL Monitor - SQL Monitor helps you and your team find issues – before they become problems
OpenSpeedTest - Broadband Internet Speed Test Unlocked!
Netumo - Ensure healthy website performance, uptime, and free from vulnerabilities. Automatic checks for SSL Certificates, domains and monitor issues with your websites all from one console and get instant notifications on any issues.