gNotify is an example script that uses GrowlNotifier to send Growl notifications from the command-line. It is basically a Python version of growlnotify.
gNotify takes the following arguments:
If -n is omitted, it defaults to 'gNotify'.
If -i and -I are omitted, the icon is defaulted to an unknown-file icon. -I overrides -i.
If -t is omitted, it defaults to 'gNotify'.
If '-' is passed as the value for -m, gNotify will read from standard input, displaying a new notification for each line.