UptimeRobot - Free Website Uptime Monitoring
HelpNDoc - What is HelpNDoc ? Easy to use yet powerful help authoring environment which can generate various documentation formats from a single source.
StatusPage.io - StatusPage.io is the best way for web infrastructure, developer API, and SaaS companies to get set up with their very own status page in minutes. Integrate public metrics and allow your customers to subscribe to be updated automatically.
Dr.Explain - Dr.Explain software is a help file authoring tool.
FreshStatus - Better status pages in 1-click, FREE FOREVER
MadCap Flare - Documentation for Any Audience, Language or Format