Ever pondered the astounding success of Starbucks or Beanie Babies, both of which turned their inventors into billionaires? Ever said to you yourself, "I could've thought of that"? Put your thinking cap on!
While some billionaires owe their fortunes to savvy investing or brilliant deal-making, many have just come up with one simple idea that proved massively popular.
http://www.forbes.com/2007/03/06/inventions-billionaires-rich_07billionaires_cz_lk_0308inventions_slide.html
http://www.forbes.com/2007/03/07/billionaires-worlds-richest_07billionaires_cz_lk_af_0308billie_land.html