In 2010, while the world was still debating the ethics of euthanasia, one designer had already moved on to the second question of how to turn it into the final ride at a theme park. Then a PhD student at the Royal College of Art, former amusement park employee Julijonas Urbonas designed what he called a "Euthanasia Coaster". The idea was as simple as it was bizarre: create a rollercoaster that would "humanely – with elegance and euphoria – take the life of a human being".

"Riding the coaster’s track, the rider is subjected to a series of intensive motion elements that induce various unique experiences: from euphoria to thrill, and from tunnel vision to loss of consciousness, and, eventually, death," Urbonas wrote on his blog about the idea, which drew widespread media attention at the time.

The basic idea was to end the life of the rider through a series of loops, pushing blood away from where it's needed with sheer g-force. The rider is given a chance to back out as they wait at the top of the coaster, but once the ride is underway it ends with demise.

"The centrifugal force drives the car upward, and you are literally pinned to the seat, your buttocks’ flesh is pressed against the ergonomic planes of the seat so hard that your whole body is almost immobilised," Urbonas writes. "Breathing requires more effort, as the ribs and the rest of the internal organs are pulled down, which empties air from the lungs."

"But most probably you are already unconscious, as this force rushes the blood to the lower extremities of the body, thereby causing oxygen deficiency in the brain."

Once unconscious, your body would continue to go along the rollercoaster, as your oxygen-deprived brain dies.