You're on Facebook one day when you notice that an acquaintance -- not someone really close, but a person with whom you're friendly -- posts a status update that seems despondent. Something like, "Man, life doesn't seem worth it. I can't take it." You look for an explanation on the person's profile, wonder if it's some kind of inside joke. But it dawns on you that it might be an honest expression of emotional pain, perhaps a cry for help.

What do you do?

It's a difficult social problem. It's not like you're a close friend of the person and would feel comfortable asking him to pour his heart out to you. Maybe you've only met him once. You very well might do nothing.

Facebook is trying to offer a new avenue to help you solve this new dilemma of the digital world. They have inserted the ability to anonymously flag someone as someone who might be suicidal. This is a very delicate user interaction design, obviously. On the one hand, Facebook wants people to be able to report real suicidal behavior, but they also don't want to create an obvious target for people who want to create mischief. Where they place the reporting mechanism as well as the behind-the-scenes processes for dealing with user reports could have very real consequences.