Pluggable notification system which supports GNTP

 Growl For Linux is a linux-compatible notification system of Growl.
 Growl is a notification system for Mac OS X. It uses GNTP (Growl
 Notification Transport Protocol) for notification.
 .
 Growl For Linux provides four kind of display styles - balloon, fog,
 libnotify and nico2.
 The display style is implemented as a plugin, so you can add a new
 display style if you want.
 .
 And more, Growl For Linux supports subscriber which will interact
 with other software. Currently Growl For Linux supports Rhythmbox.