You can tag people using the @ sign. This will also send them an alert that you tagged them so they'll look at your post. Let's say they are not watching the thread (formerly called "subscribed"), and you want to get their attention because you know that they know something about the subject. You could simply type: Hey @Turbo, what do you think of this? Now I will get notified that you tagged me in your post (if I have notifications set for tagging) When you start typing after the @ sign, it will pop up a window that lets you select the user, and you can narrow down who that user is as you keep typing. How cool is that!
I think I got it partially right. I get the alert that says you mentioned me, but I didn't get an e-mail alert...besides the one about the new post.