Spanx Founder, 41, is Youngest Woman Ever to Make Forbes Billionaires List

A woman who couldn't pass her law school admission test but went on to create the undergarment brand sensation Spanx is the world's youngest self-made female billionaire, according to Forbes Magazine.

Sara Blakely, a 41-year-old graduate of Florida State University, will appear on the March 26 cover of Forbes.

Blakely started Spanx by herself with $5,000 in the year 2000. The Spanx website explains it this way:

"Putting Her Butt on the Line Pays Off: Spanx founder Sara Blakely was getting ready for a party when she realized she didn't have the right undergarment to provide a blemish-free look under white pants. Armed with scissors and sheer genius, she cut the feet off her control top pantyhose and the Spanx revolution began!"

Forbes reports that four Wall Street banks have recently valued Spanx at an average $1 billion, a sum Forbes corroborated with assistance from industry analysts.

"Blakely owns 100% of the private company, has zero debt, has never taken outside investment and hasn’t spent a nickel on advertising," Forbes reports.

By making Forbes' list, Blakely also joins an elite club of American women worth ten figures on their own, including Oprah Winfrey and Meg Whitman.