MailCall notifies you of new mail within 10 seconds of a change in your /usr/spool/mail file by playing the sound of your choice and displaying only the FROM and SUBJECT lines of the mail in a scrolling window.
MailCall remembers the sound you choose between logins in the dwrites database.
Its a very useful app for keeping an eye and ear on your incomming mail without having to clutter your screen with the NeXT Mail window every time there's new mail.
I welcome your comments and suggestions, but unfortunately I won't have an email address much longer so I won't post it. I don't own a NeXT either, but the good folks at work let me use one.