EasyNetMonitor is a small and simple network monitor that runs in the system tray and enables you to ping the online status of one or more websites or IP addresses. If one of your monitored devices stops responding, you can be notified via system tray balloon message, sound alert and/or customizable email notification sent to and email address of your choice. In addition to real-time notifications, EasyNetMonitor can also maintain a log file of all connection attempts and errors.

EasyNetMonitor is the easiest and quickest way to get information on-line about computers in your local network!
You don't need to install it, just download and use free network monitor EasyNetMonitor anywhere
EasyNetMonitor is only 1 Mb (only one file)
You can monitor any internet host
Email notifications (your computer name should be in English letters only!)
Sound notifications
Event log
EasyNetMonitor is free