If it is not plain to everyone, here is some evidence:
Sony Picture’s Scott Rudin exec emails: http://deadline.com/2014/12/scott-rudin-apology-sony-hacking-barack-obama-1201320321/
His racially insensitive emails were posted after the network and all servers were hacked. even after several years go by the emails have surfaced.
SEP = Security Equals Privacy
This scenario can be repeated: Google and Twitter accounts were taken from Mat Honan http://www.wired.com/2012/08/apple-amazon-mat-honan-hacking/all/ due to an Apple – Amazon security flaw (nothing to do with Sony Pictures network hack).
YikYak app claims anonymity:
Even supposed anonymous service Yik Yak on hackaday.com http://hackaday.com/2014/12/10/yik-yak-mitm-hack-give-the-dog-a-bone/ there is a specific Man-In-the-Middle (MITM) attack that removes the anonymity in the Yik Yak service:
from Wikipedia entry: Yik Yak is an anonymous social media app. It is available for iOS and Android and it allows people to anonymously create and view “Yaks” within a 10 mile radius.[1] It differs from other anonymous sharing apps such as PostSecret and Whisper in that it is intended for sharing primarily with those in close proximity to the user, potentially making it more intimate and relevant for people reading the posts. (the YikYakapp site was down at this writing – as I usually do not like to quote from Wikipedia)
Here is a Gizmodo article about the Yik Yak app not being anonymous and never will be.
I believe that even Tor (an anonimizer for the web) can be deconstructed by hackers… My full intent for this article is to state there is no anonymity on the Internet Do not beleive anybody that claims different.
And your email especially can be found – so be careful what you write people, assume the world will read it (i.e. your enemies and friends).