Low enough gravity and you can have human wing-powered flight.
I don't know how much of a sport it would make, but at low enough gravity you can run on water. If you can manage to arrange it, have a competition like high jumps--keep raising the bar (in this case, gravity) until only the top person makes it across.
In a spin "gravity" environment that isn't too big you could have some interesting variations on marksmanship--put the target far enough away that a high arc is needed to hit it which will introduce some tricky Coriolis effects, and some wind effects also. (If you have enough vertical space for this sort of thing you have enough that you will get differential air movement.)
Basketball would become a very different game in a quite low gravity environment. Use a basket that is at an angle that can only reasonably be hit by someone who has jumped well above the court.
In spin "gravity" environments where the center is hollow you could have axial jumping competitions--likely with a power assist of some kind. So long as you're close enough to the center you can use aerodynamics to steer, but if you get too far away you're going to fall. Either do this in low enough "gravity" that the fall is safe, or wear a parachute. The objective is to get as far as possible from your jump point--if you're using a chute the deployment altitude would be preset for everyone to keep people from trying to stretch the glide by pulling too early and risking the chute collapsing.
In a low spin "gravity" environment that is open inside, jumping competitions--a power assisted jump, your objective is to land as close to the pin as possible--that is on the other side of the environment. (Yes, you're taking off with more energy than you can safely land with--it's going to bleed off in the air. Safety is determined by terminal velocity.)