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.
SEO PowerSuite - Get all SEO tools in one pack - download free edition of SEO PowerSuite and get top 10 rankings for your site on Google and other search engines!
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Monitor Backlinks - Easy Link Management - SEO Tool for automatically checking your backlinks.
Better Uptime - We call you when your website goes down
SEO SpyGlass - SEO Spyglass is a website backlink checker tool & link popularity checker.