The LeViteZer magnetic anti-roll suspension system on the track
It got U.S. patent 2017, it was expensive, but rewarding expertise to see trough the hole process and I think this invention will have use also beyond the small radio controlled cars.
The original LeViteZer anti-roll suspension system video.
LeViteZer anti-roll suspension system resellers (currently out of stock)
There is always something interesting under work