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.

Zabbix - Track, record, alert and visualize performance and availability of IT resources

AppZero - AppZero is a monitoring and migration tool that allows users to keep track of different applications and servers in both simple and complex IT environments.

RedGate SQL Monitor - SQL Monitor helps you and your team find issues – before they become problems

Nagios - Complete monitoring and alerting for servers, switches, applications, and services

CULA - A webmonitoring solution for beginners and pros.