Ask HN: In an interview, what do you answer when asked “tell us about yourself”

This is by far my weakest point in an interview. I usually do ok when answering concrete questions but when this moment comes, where I have to do some kind of general presentation of myself, I never really know what to say, or what the other side expects to hear.

What do you answer? Do you start from the end or from the beginning? Do you have a speech prepared? How long do you talk, how technical or detailed do you get?

Do you know any example (e.g. video) of what makes a good self presentation?

I feel I really need to prepare this, any pointers or stories appreciated.