Unlike other forms of notification, Snarl does not hijack the current focused window, nor does it force the taskbar to be visible. Notifications can either be cancelled by clicking on them, or left to disappear automatically if ignored for a period of time. Messages are extensible too: Snarl will notify the application which displayed the message if the user clicks it.
Snarl now supports extensions - small code modules that run within Snarl's process space - which can be used to extend functionality of existing applications without requiring modifications to the application itself.
Extensions are already available for the following applications:
* MSN Messenger (notifies when people sign in)
* Microsoft Outlook (notifies when new mail is received)
* The Windows System Tray (translates the contents of balloon tips)
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