Yahoo has been searching all of our e-mails

"Yahoo Inc last year secretly built a custom software program to search all of its customers' incoming emails for specific information provided by U.S. intelligence officials, according to people familiar with the matter.

The company complied with a classified U.S. government demand, scanning hundreds of millions of Yahoo Mail accounts at the behest of the National Security Agency or FBI, said three former employees and a fourth person apprised of the events.

Some surveillance experts said this represents the first case to surface of a U.S. Internet company agreeing to an intelligence agency's request by searching all arriving messages, as opposed to examining stored messages or scanning a small number of accounts in real time.

It is not known what information intelligence officials were looking for, only that they wanted Yahoo to search for a set of characters. That could mean a phrase in an email or an attachment, said the sources, who did not want to be identified."

 Me personally, I have nothing in my Yahoo accounts to be worried about.  However, EVERYONE has something that taken out of it's proper context can lead to more intensive scrutiny.  Even Great Grandmama who is exchanging knitting patterns and recipes can be considered a threat by an aggressive automated search algorithm that uses pattern recognition instead of real people.

Considering the shear volume of mails, that is the only way they can be checked.  By a computer that doesn't know about knitting or cooking or about how cute great grandson playing in dads workshop with firecrackers is sudden;y a new terrorist plot.

And like that, your Great Grandmother is on a watchlist.