Google's Report Spam button is actually pretty close to that. If the message has a List-Unsubscribe header, it offers to use that after hitting the Spam button.

Google's Report Spam button is actually pretty close to that. If the message has a List-Unsubscribe header, it offers to use that after hitting the Spam button. And usually they don't really take 10 days, but that's the limit the law permits so they give themselves as much wiggle room as possible.