A man once designed a 'Euthanasia Coaster', which is... well, exactly what it says on the tin.
The imagined ride was dreamt up in 2010 by designer Julijonas Urbonas, from Lithuania, who billed it as a 'hypothetic death machine in the form of a roller coaster, engineered to humanely - with elegance and euphoria - take the life of a human being'.
He continued: "Julijonas Urbonas designed this roller coaster called the Euthanasia Coaster. It's capable of holding up to 24 passengers. Once they're all on board there's a slow ascent to the top, which is 510 [metres] in the air - that's just a little bit smaller than the tallest building in America.
"Once they're at the top it gives everyone the decision to stop and go back down safely. After that, everyone has to manually press a button to start the ride.
"Then it falls at a speed of 223 miles per hour, and goes through seven loops that keep getting smaller."
According to Urbonas' website, he is an artist, designer, researcher, engineer, found of the Lithuanian Space Agency and Associate Professor at the Vilnius Academy of Arts.
He explains: "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."
The project, which was awarded the Public Prize of New Technological Art of Update 2013, has become a 'unique media phenomenon' since it was unveiled in 2010.
Urbonas explains that riders are 'slowly towed to the top of the drop-tower', which takes a while as the ride is about half a kilometre long - in turn giving people time to contemplate their decision.
He continues: "You relax and press the FALL button. Whirrr... swish - the ultimate surrender to gravity!
"No, you realize, in fact it is even greater than just giving up, as in the blink of an eye you enter the heart-line, the whirling element of the coaster track, where your heart stays roughly in line with the centre of the fall trajectory.
"In other words, your body spins around the heart while you fall. Gravitational choreography!"
The track then straightens as riders enter the roller coaster's several loops, during which time their boy becomes immobilised, their face starts drooping down and breathing requires more effort.
"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," Urbonas says.
"It is exactly this cerebral suffocation, also known as cerebral hypoxia, that is going to kill you," he explains, concluding: "The rest of the ride [...] proceeds with your body being numb, ensuring that the trip ends your life. You die, or, more accurately put, your brain dies of complete oxygen deprivation, a legal indicator of death in many jurisdictions.
"The biomonitoring suit double-checks if there is a need for the second round, which is extremely unlikely, as the result is guaranteed by seven-fold repetition."