Alex Blumberg made his early career by helping build two of the most successful shows in radio and podcasting: Planet Money and This American Life. In 2014, convinced that podcasts could make money, he walked away from the safe umbrella of public media to start a new media company with co-founder Matt Lieber. Every doubt, triumph and humiliation of building the business was documented on the podcast Startup, which included the back-and-forth over how the company got its name: Gimlet. Many more successful podcasts followed, and five years after launch, Gimlet sold to Spotify for roughly $200 million. PLUS in our postscript "How You Built That," after years of researching how women's shoes wreak havoc on the joints, Casey Kerrigan quit her job in medicine to start 3D printing more comfortable designs: Oesh Shoes.