Email is an old method of communication — yes, it's been here since 1965 with the first messages on the Arpanet being sent in 1971 — but the way it operates is still as much of a mystery to the average punter as it was back in those days.
The original author of the mail transport agent Sendmail, Eric Allman, has been confirmed as one of the keynote speakers at the Australian national Linux conference in 2011.