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.
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
HelpDocs - Educate your users with a super simple knowledge base that’s built for teams just like yours.
Better Uptime - We call you when your website goes down
phpMyFAQ - phpMyFAQ is a world’s most popular mobile-friendly, feature-rich and open-sources FAQ software that uses PHP 5.