First, there was the Gravity Plane, a concept so obvious, I'm surprised it took this long to make it to the almost-practical stage. The video tells the whole story.
Now, we have the Air Trailer, a brilliant application of one of the most straightforward and easy phases of flight, the aerotow. Their website needs work, but the video is just as convincing as the one on the Gravity Plane.
Both projects probably need investors. I hope I'm not too late.
