Why sexting and a Stanford class led a group of former fraternity brothers to create Snapchat. Read More. : Billy Gallagher Contributor Billy Gallagher is a former TechCrunch staffer whose first book "HOW TO TURN DOWN A BILLION DOLLARS: The Snapchat Story by Billy Gallagher" is on sale now. Gallagher previously worked as an analyst at Khosla Ventures. Billy Gallagher is a former TechCrunch staffer whose first book "HOW TO TURN DOWN A BILLION DOLLARS: The Snapchat Story by Billy Gallagher" is on sale now. Gallagher previously worked as an analyst at Khosla Ventures.