I have not re read all posts, but I do not think someone have put it this way before: A homebuilt quadrocopter/multicopter type vehicle. Why? Think about what flying toy many young (and not that young) people play with. Quite some of them assemble their multicopter and tune the controllers themselves too. Some modify ready made vehicles. The next step is then something to not fly first person view, but actually fly in person. Quite some airplane builders aspired from model airplane building. Tomorrow it might be full size multicopters.