Basically, the more email addresses you could come up with, the better you'd be in Emaility. You created one big "mother" account and an infinite amount of children accounts. Every child would receive a random password in regular intervals and players had to enter that password to feed the children. The bigger your army was, the higher your chances of victory were when attacking other players.
A handful of people played it, but I killed it off myself pretty soon, I don't remember exactly why, but I think it caused a problem with my provider back then.