Möbius coaster
From ThorxWiki
The world has already seen Möbius Loop roller coaster, however these seem to run as parallel tracks.
bah.
I want to see a true Möbius strip coaster. ie, where the track is suspended by the sides, and the actual rails run both above and below, meaning you complete the same loop twice - once inverted compared to the other.
Track design may be complicated to ensure G-forces at all points are safe and sane for riders?