How many times have you tried to browse to one of your favorite sites, only to find it is currently down? It can be especially frustrating if the site is vital for some part of your daily life, such as your online banking. With no way of knowing when it will be back up, the only thing you can do is check on it periodically. That, or you could have a service automatically contact you when it is back online.
Ding It’s Up is a handy little web tool that will notify you via email, text message or Twitter when a specified site is back online. All you need to do is plug in the domain and how you’d like to be contacted. They will even notify you when it goes back down if you like.