I’m a huge roller coaster fan and even have a sister blog dedicated to 3D printing (this entry appears on both sites). One of the more recent advances in roller coaster technology has been the use of magnetic launches as opposed to the old school lift hill (think click, click, click up the hill). To be fair launch does go back 50+ years with examples like the Tidal Wave coaster I used to ride at Six Flags Great America as a kid. This defunct ride actually used a falling weight and pulley system to launch the train with a deafening “clank” as the weight hit bottom! One of my personal current favorite launch coasters in Cheetah Hunt at Busch Gardens Tampa where the launches are used to mimic the acceleration and movements of a cheetah.