Downalarm

Down Alarm is a easy to use but effective tool that runs on your computer out of the way. Just press the "New" button and enter your website's domain name.

Press the start button and Down Alarm will try to access your website. If your website is offline, Down Alarm will show a red LED in your system tray. Otherwise, Down Alarm will show a green LED.
Down Alarm will even check as many websites as you wish, and it will keep the connection information in a log file that you can look at when it is convenient for you.