Note 1: Boeing once toyed with a blended wing-body, a sort of flying wing, to produce dramatically better aerodynamics and fuel efficiency. Passengers would have sat in a wide cabin, rather like a small amphitheater. But tests with a mock-up produced such a negative reaction that the company dropped the technology, except for military refueling aircraft.
1. https://en.wikipedia.org/wiki/Blended_wing_body 2. https://en.wikipedia.org/wiki/Boeing_X-48