Buyout offer: $15 billion from Microsoft
What happened: At a Paris tech conference in December of 2010, a Microsoft executive told reporters that three years earlier, Steve Ballmer offered to buy the social network for $15 billion. Why? According to the executive, the company reminded Ballmer of the way Microsoft used to be back in the day (we assume that's a compliment). When Zuckerberg turned down the money, Microsoft countered with a $240 million investment for a minor stake in the company. You know the rest of the story: Facebook became the biggest social network in history with over 700 million registered users; it brings in $2 billion in revenue each year; and is now worth $100 billion after its IPO.