By the house of the future: http://www.youtube.com/watch?v=7mj26QFW6JA

I work for an email security company. Let's just say SPF is great and all, but it's never going to hit the rate of acceptance needed to thwart this neverending garbage. BATV might be what you're talking about (Bounce Address Tag Violation) which is starting to see some implementation around the email scene.