Website going down unnoticed is a nightmare for website owners. We have been using an internally created software to monitor all of our websites. We recently packaged it and released it to public as a SAAS. http://www.GotSiteMonitor.com * 5 FREE website monitors * 5-minute monitoring interval * 12 global monitoring locations * Email/Sms/Phone alerts (currently limited to US/Canada numbers) * Html content check * Maintenance window support We hope this service will be useful to all website owners. Feedback, requests, and suggestions are highly appreciated. Thank you.
Website monitoring is hugely important. I'd also add StatusCake.com into the mix which, as far as I know, is the only service to allow you to monitor unlimited websites and URLs for free with alerts via SMS, email, Twitter, iOS & Android push notifications.