Have you been wondering what’s going through 27-year-old billionaire Mark Zuckerberg ‘s head as the company he started in his Harvard dorm room eight years ago files for IPO? You don’t have to wonder — Zuckerberg just shared a picture of his desk at Facebook HQ on his Timeline with a simple message: “Stay Focused & Keep Shipping.” It’s pretty clear what the message means: Zuckerberg is reminding himself to think about his product — the social network that unites more than 800 million people across the world — rather than today’s news from Wall Street, which could make him one of the richest men on the planet. Read more »