Buyout offer: $140 million from Facebook
What happened: At one point, everyone wanted to buy Foursquare. Microsoft was interested; rumors of Yahoo! putting together a $100 million offer were spreading; Facebook wanted to bring it into the fold. All the companies were turned down, of course, but things got interesting at the Le Web 10 conference when Foursquare CEO Dennis Crowley confirmed, in so many words, that Facebook wanted to spend around $140 million on the check-in service. After the talks ended, Foursquare raised $20 million in financing, and Facebook launched its own check-in service.