There is always Elite Dangerous: * Normal flight is mostly Newtonian, but with a bonus to acceleration and rotation if your speed is within an optimal range, and upper limits on thruster spatial and angular velocity for gameplay balance. Gravitation also has a speed limit, although both limits only apply in their respective directions of acceleration, so with enough time they can be combined to reach any speed (a community sport known as Speedbowling). * Interplanetary travel has new physics of its own, allowing speeds up to 2001c, and the effect of gravitation now limits your cruise acceleration (as opposed to applying orbital mechanics). This also limits deceleration, which can leave you physically unable to slow down if cruising past a planet. * Interstellar travel has no spatial physics at all, just a fixed total time to arrive at a destination star (about 30 seconds including charge time), although it does have an interesting fuel expenditure curve which is affected by ship mass. One tank of fuel can get you anywhere in the galaxy in theory, if you're willing to make thousands of tiny jumps, although in practice this is only true around the galactic core due to lack of available star density elsewhere.