When Ruchi Sanghvi went to Facebook for an interview in the summer of 2005, the social network's office was a makeshift one, above a Chinese restaurant in Palo Alto, with wall to wall graffiti. A blackboard at the entrance advertised vacancies for engineers. Plenty of people were working around the space, many of them students. It was difficult to tell who worked there and who didn't, she recalls. But what was unmistakable was the sheer energy in the room. She reached the office around noon, the day of her interview. Her interviewers weren't in yet. When Mark Zuckerberg finally walked in an hour later, he spoke to her for around an hour and a half. "He (Mark) asked me questions like if you could just take two things with you to Mount Everest, what would they be. He was tasked with keeping me occupied," she says. Her actual interviewers walked in only around 3 pm.