HTTPS Everywhere - Chrome extension that encrypts and secures your browser
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.
Smart HTTPS - Automatically changes HTTP addresses to the secure HTTPS, and if loading encounters error, reverts...
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
HTTPZ - HTTPZ is meant to be unobtrusive and lightweight.
Better Uptime - We call you when your website goes down