Growl is a great new application service that allows any Mac OS X application to present notifications in a unified manor. This allows notifications for iChat, Mail, iTunes and other applications to present a unified notification. So now instead of having some applications bounce their dock icons, some opening windows, and others putting badges on the doc icon, there can be an integrated notification system.
When I was working at Apple, I though that this should have been built into the OS. I though that there should have been a control panel that would have allowed the user to change what the default behavior would be for notifications. I thought that this could have been change to beep, flash the menu bar, or run an AppleScript. This would allow emails to be sent for notifications on headless server computers.Â It looks like Growl can solve this problem.
Here is a link to a script that allows Growl to show notifications for iChat.
I was not able to get the Mail.app bundle to work, but I was able to get the AppleScript to work. It runs when ever a new mail is received.
Here is a link to a command line program that will send notifications to Growl. This is will allow these notifications to be used in shell scripts.