StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Cymbal - Music discovery powered by friends
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.
humit - A social networking app for music sharing and discovery.
UptimeRobot - Free Website Uptime Monitoring
Better Notes - Simple notes app that ties notes together with #hashtags