Back in the 1960s, I remember seeeing a car-plane that one could assemble and take off/land from any road. I do not recall what it was called (UPDATE: It was the 1956 Aerocar, designed and built by Moulton Taylor), but the idea has always appealed to me. Now, I see that I am not alone in this idea. Author and roboticist Daniel Miller has written an article for Popular Mechanics wherein he takes on the idea of flying cars.
Although he judges that "...it may be another hundred years before you can score that most badass symbol of the space age—the flying car.", he also details some of the possibilities currently under development. I found the article fascinating. Read the whole thing and see what you think. Hat tip to techno-geek law professor Glenn Reynolds.