UptimeRobot - Free Website Uptime Monitoring
Nagios - Complete monitoring and alerting for servers, switches, applications, and services
Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Gitwin - Enable your Windows system as a powerful and secure Git repository. Supports ssh, http(s) transports. Gitweb with highlighter and gravatar support available.
Uptime Kuma - A fancy self-hosted monitoring tool.
Zenoss Core - Zenoss (Zenoss Core) is an open source application, server and network management platform based on...