I was browsing through RFC 821 today, trying to look at what I think might be a bug in part of Qpsmtpd, and I came across some fun deprecated verbs:
SEND
This sends the message direct to the user's terminal. Umm, yeah.
SOML
This sends direct to terminal if the user is logged in, or mails it.
SAML
Send and mail.
TURN
Switches the sender/receiver ends around so the sender is now the receiver, and vice-versa.