In the 1990's, Stacy Madison and her boyfriend Mark Andrus were selling pita sandwiches from a converted hot dog cart in Boston. They decided to bake the leftover pita into chips, adding a dash of parmesan or cinnamon-sugar. At first they handed them out for free, but soon discovered that people were happy to pay for them. So they eventually decided to leave the sandwich cart behind and launch Stacy's Pita Chips. They hoped the brand might grow into a modest regional business—but it kept growing. Roughly ten years after the launch, Stacy's sold to PepsiCo for $250 million. PLUS in our postscript "How You Built That," how Prerak Juthani and some friends from college took organic chemistry to the next level with REACT!, a board game that aims to demystify the stigma of molecular science.