NIXStats - SaaS monitoring tool for window/linux servers and websites. Think up-time robot but with more features.
AppInsights - Gain insights and make informed decisions by letting you consolidate, visualize, and share your...
Server Monitoring - A server monitor is a tool that monitors your server and website on close intervals and reports to you if it's inaccessible.
freeboard - An open source real-time dashboard builder for IOT and other web mashups.
mackerel.io - mackerel.io is a server and application performance monitoring platform.
Geckoboard - Get to know Geckoboard: Instant access to your most important metrics displayed on a real-time dashboard.