It looks like we are getting closer to the "caller ID for e-mail".
The computer industry is fast-tracking a system called e-mail authentication, which will attempt to do for e-mail what caller ID does for telephone calls. E-mail authentication will assure the recipient that the sender actually is the person identified in the message header.
Sounds good, but it also sounds like it would be edging closer to web-surfers losing some of the anonymity that can make the internet a safe place to be. I guess it would really depend on how it is implemented.