Airbnb is a great startup success story. It's reportedly raising a new round of financing that will value the company around $20 billion. But when Airbnb was first getting started in 2008, the founders struggled and would-be investors snubbed their idea. The founders shared their first pitch deck with an MBA student, back when it wanted to be an air mattress rental company.Airbnb was initially called AirBed&Breakfast.