I think the movie Minority Report had a really cool concept of a sort of "semi-suspended" railway: The machinery that connected to the rails could rotate all ar

I think the movie Minority Report had a really cool concept of a sort of "semi-suspended" railway: The machinery that connected to the rails could rotate all around the train car, so depending on the environment, the tracks could go below the car, above the car, or even beside the car, which would allow it to use sheer walls as "ramps". I'm not sure if something like this would in any way be physically feasible, but if yes, it might solve the cost problem, because part of the rails could then be run on the ground. (Maybe a less sci-fi version would be a "hybrid" car that has a second set of wheels on the underside and could switch between ordinary and overhead rails as needed?)