I day dreamed about an inverted guided conjoined articulated hovercraft; you can call it a train I guess.
It hangs from flanges attached to the ceiling. Jets of air flow onto the flanges to make it float like a hockey puck on a air hockey table. The train has two floors so passengers can go upstairs if they're in good shape and want to avoid crowding below. I could have day dreamed about a magnetic levitation train but I don't like how very long arrays of strong electric magnets along the whole track.
The air jets tilt slightly to make the train move forward. There is also wheels inside the drive unit incase there is a power cut or engine failure.
The beauty of the train like vehicle would be that there is no wheels grinding on rails. The track doesn't get worn down by metal wheels.
