Some news sites including Buzzfeed and The Atlantic have proposed adding a like button to emails and the reality is, it wouldn't be so hard to do. According to Pete Resnick, one of the directors
at the Internet Engineering Task Force (IETF), the engineering standards group that manages email, a like button for email is "perfectly plausible." Using an RFC 3798
extension, when an email user 'liked' an email, then an auto trigger could send out an email to everyone else on the thread.