Not gonna make a new thread for this but have you guys seen this?
http://imgur.com/gallery/BXO3tA roller coaster designed to kill its passengers. Insead of lethal injection or eletrocution.

The concept design of the layout begins with a steep-angled lift to the 510-metre (1,670 ft) (0.317 mile) top, which would take two minutes for the 24-passenger train to reach.From there, a 500-metre (1,600 ft) drop would take the train to 360 kilometres per hour (220 mph), close to its terminal velocity, before flattening out and speeding into the first of its seven slightly clothoid inversions. Each inversion would have a smaller diameter than the one before in order to maintain the lethal 10 g to passengers while the train loses speed. After a sharp right-hand turn the train would enter a straight, where unloading of corpses and loading of new passengers could take place.
The Euthanasia Coaster would kill its passengers through prolonged cerebral hypoxia, or insufficient supply of oxygen to the brain.[1] The ride's seven inversions would inflict 10 g on its passengers for 60 seconds – causing g-force related symptoms starting with gray out through tunnel vision to black out and eventually g-LOC (g-force induced loss of consciousness). Depending on the tolerance of an individual passenger to g-forces, the first or second inversion would cause cerebral anoxia, rendering the passengers brain dead.