Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
statuspage - A simple self-hosted status page site with an API written in Django under the BSD license.
Kayako - Help Desk Software and Customer Service Software by Kayako. Improve customer satisfaction, increase sales.
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.
MeisterTask for Freshdesk - Meister your customer support tasks
UptimeRobot - Free Website Uptime Monitoring