Wetty - Terminal over HTTP and HTTPS.
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.
Shell In A Box - Shell In A Box is a web based AJAX terminal emulator that can export arbitrary command line tools...
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Bastillion - Bastillion is an open-source web-based SSH console that centrally manages administrative access to systems.
Better Uptime - We call you when your website goes down