Roelof and i had long discussions in the past, around someway to get people to update information on people while growing the db and still having people contribute.. Interestingly, spocks simple sounding approach might be perfect.. in a day when everybody vanity googles themselves, and when the facebook/myspace/twitter generation have 0 qualms about informing the world what they are doing 24/7, the simplest way to populate a db with information about people, might just be to let them fill the info in themselves..
Not surprisingly, I found myself on spock. But I haven't been able to find most of my other friends in college. As I was filling in random tags as vaguely as possible, they asked one semi-disturbing question though: "Where were you born?". :-\ I'm sure I've seen that question before. As one of the choices for a security question.