Ok, this is the hedgemeister being really nutty here, but this makes me think of Planet of the Apes (the original, not the remakes), in which there's some sort of plague that kills off everyone's dogs and cats, but doesn't affect apes, who are then taken as pets instead. For some reason this causes them to evolve and take the place of humans as the dominant species. The law of unintended consequences! So along the same lines, if coffee beans go extinct, what if a synthetic alternative is created which accidentally makes humans telepathic, or better yet, removes their need for sleep? If there's a sci-fi story in there somewhere, please feel free to take it and run with it. As for me, I think it's time for a lie down . . .