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.
Coupofy - Coupofy is USAs number 1 trustworthy deals and coupons website.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Giftwhale - Giftwhale allows you to create personalised wish lists online.
Better Uptime - We call you when your website goes down
TrackIf - Alerts you if the price of your favorite products drop