An electronic mail system and method enables the originator of a message sent by electronic mail to select a date, time, or event at which the message and all incarnations of the message to self-destruct, regardless of the number and types of computers or software systems that may have interacted with...http://www.google.com.au/patents/US7149893?utm_source=gb-gplus-sharePatent US7149893 - System and method for enabling the originator of an electronic mail message to preset an expiration time, date, and/or event, and to control processing or handling by a recipient
