Now for something completely different... XB-70 Valkyrie. I wouldn't say it's my favorite but an article in Boy's Life (Flight of the Valkyrie, 1962) inspired my interest in aviation. It was the USS Enterprise of the era.
Favorite cute-ugly/failure, XF-85 Goblin. I sure as hell wouldn't want to fly one. I saw one on static display at Offutt and I can't imagine that the short coupled little thing could be controlled. All before fly by wire so no computer help no less.
The key elements in human thinking are not numbers but labels of fuzzy sets. -- L. Zadeh