What does the richest person you personally know do for a living?

I've met a few very wealthy people, as in celebrities at autograph signings etc., but as far as knowing any wealthy people [b]personally[/b], I've been too isolated over the past several years to be sure of my acquaintances. None of my family appear to be doing all that well. However, I'd be willing to guess that if I'd kept in touch with former classmates, I'd find some of them to be highly successful and financially well off, especially those I knew who were born to wealthy families.