Is there any way to configure Mail.app to permit the sending of mail messages from one Mac computer to another Mac computer on the same LAN without resorting to an external mail server? It seems ridiculous to me that I need to send an email to my wife (who sometimes needs information in electronic form or copies of emails) via the mail server associated with our ISP. It would be so much simpler if I could use Bonjour and send the email more directly to her computer!