There's nothing private about email. Benjamin Mako Hill
hosts his own email. You might think that would keep him
free of Google's privacy invading clutches. Yet
as he points out, more than half his mail comes from or
gos through a Google account. Which means the bots get to
read most of his stuff.
Despite the fact that I spend hundreds of dollars a year and hours of work to host my own email server, Google has about half of my personal email! Last year, Google delivered 57% of the emails in my inbox that I replied to. They have delivered more than a third of all the email I’ve replied to every year since 2006 and more than half since 2010.
Google Has Most of My Email Because It Has All of Yours | copyrighteous.