When it comes to the ranks of the world's billionaires, the fairer sex is still very much the rarer sex. In 2008, Forbes counted 99 female billionaires, 16 more than last year, but still representing slightly less than 9% of the world's 1,125 billionaires. Just making it into the ranks of this uber-exclusive club is enough to turn these women into some of the most envied people in the world.

But while there is much to desire about their well-funded lifestyles--shopping sprees, luxury getaways and personal assistants to name a few--it isn't just their bank accounts that make us covetous. Many of these notable women have influential careers, respected philanthropies and admirable ambition. Those honorable traits plus extraordinary wealth make these fascinating women especially worthy of our admiration--and envy. In honor of these women, we selected the dozen we'd most like to be, or at least meet.

Only 10 women billionaires are self made, having built their vast fortunes themselves. Of those, we've picked four to highlight. Oprah Winfrey, the unparalleled queen of daytime television, rose from hardscrabble beginnings in rural Mississippi to become one of the most respected media personalities in U.S. history. Oprah's power as a tastemaker has helped her amass an estimated $2.5 billion personal fortune.