Today’s invention extends the idea of a rotating-wheel space station, in which the spinning can press objects against the interior of the outer surface of the torus, creating artificial gravity.
Instead, I foresee the use of rocket-powered race vehicles, running on the flat inner surface, as shown.
Races could be viewed through transparent sections of the ‘roof’ of the station.
The spectators would enjoy high-speed contests with no air resistance…so the vehicles could be almost any shape.
There would also be the added thrill of knowing that one false move would mean vehicles disappearing off into space.
Too high a speed could cause the crowd to be pinned to their observation couches or float around uncontrollably (depending on the race direction).