Lyman Spitzer talks about his concept of trying to plan a transcontinental transportation network as a doctoral student.

Spitzer:

Well, I wasn't frustrated. It didn't get very far. I don't quite know how high my hopes had been when I started. I don't suppose I really expected to have a particle accelerator built in the attic of the physics building during my junior and senior years. But it was to sort of layout what might be done. But in view of the experimental difficulties, I tried to make up for it with an elegant theoretical analysis of what I'd done. That in itself wasn't too successful either.

I planned out another thing in that period. On a trip out west I got very much interested in planning a transcontinental transportation network, which it seemed to me was the sort of thing ultimately one would have to go to, with tubes connecting different cities, using electromagnetic suspension, with cars accelerated and decelerated electromagnetically. I’d planned for integrating this inter-city network with the local transportation within each city. The concept was to apply to transportation the same diversification and branching philosophy that one uses in telephone systems. Small cars would travel in tubes between cities, and end up various places within the city, and might even, in tall buildings, go up and stop at one of the high floors, in a skyscraper. I spent an enormous amount of time just thinking about various practical problems, how all this might be done.

I told my father about this, and he began to think I was going off the deep end, and made me promise I wouldn't think about this scheme for another three of four months.