The president of this company took an idea for a product and ran with it - when she was 8 years old! Her company, PuterBabies, sells plush toys that sit atop computer monitors. Two years later, she has outlasted many dot-coms and is breaking even. With her experience and marketing savvy, she'll be ready to retire by high school.
http://www.puterbabies.com
http://www.nandotimes.com/technology/story/126718p-1334235c.html