Are My Sites Up? is a web-based application for tracking the up time of web sites and sending notifications when they are down. If you need to know immediately if a site is down completely or just unavailable to you, a service like Down For Everyone Or Just Me? is a great tool. If you'd like to monitor a site more consistently and get notifications when there is an interruption in service you'll need a more advanced tool. Set up a list of up to 50 sites to monitor at the Are My Sites Up? web site. In addition to being able to check the status of the sites on the Are My Sites Up? control panel as seen in the screenshot above, you can also set it to email you and send you an SMS update when one of your monitored sites is down. The service requires no ownership of or modification to the web sites you are monitoring, you can use it on your own site or any site you want to keep an eye on.