Comment by sbierwagen

It's easy enough to build a hoverboard with spinning magnets over copper plate: https://www.youtube.com/watch?v=HSheVhmcYLA

As you can see, it's not actually that fun to ride. It hovers in every direction, like standing on an ice cube. The reason ice skates and roller blades work is they have low friction only along one dimension, so you can still apply force to the ground along the normal vector.