Today I've received several spam messages of this form:
%TO_CC_DEFAULT_HANDLER
Subject: %SUBJECT
Sender: "%FROM_NAME" <%FROM_EMAIL>
Mime-Version: 1.0 Content-Type: text/html
Date: %CURRENT_DATE_TIME
%MESSAGE_BODY
This is pretty funny; they forgot to insert the actual spam into the template. You'd hope that anti-spam detectors would catch on to this pretty easily.