>>> when a woman named sarah blakely was just 27 years old and a saleswoman, she had a good idea. undergarments that work hard to put stuff back where it was perhaps and flatter every figure. she turned that good idea into the very successful company called spanx. well, now of course they're ubiquitous. they've sold millions. they've made billions. and tonight sarah blakely has become the youngest woman to join the previously exclusive, mostly male club, the "forbes" billionaire list.