Mark-as-Spam buttons have been a standard feature in webmail sites for quite a while now - but what to do when the sender is someone you know, but the message is clearly spam? The old answer: write to your friend, or maybe call them (because their email is clearly on the fritz), recommend that they go through the painstaking process of verifying identity, changing passwords, apologizing to friends, and so on. The Hotmail team thinks (and I agree) that this event instead needs its own button: "My friend's been hacked!" This case meets the requirements to be button-worthy: it accomplishes a set of functions that'd be inconvenient to perform separately; it presents the button to those who are in the best position to judge whether it needs to be pressed; it's clear what the button will do, and when it should be pressed; it even adds to the internal "smarts" of the webmail system, just like spam buttons. Overall, a very fine addition - welcome aboard, friend's-been-hacked button!