1. Sinkholes STR / AFP / Getty Images Ever done something so embarrassing you wished the ground would open up and swallow you? Well, the good news is you don't have to experience any embarrassment and can skip straight to the ground-swallowing fun. The bad news: You have no control over this earth-devouring nightmare.Sinkholes typically form when rain falls on to an area of land where it has nowhere to drain but into the subsurface. The water slowly erodes the surface below the non-porous ground, causing a hole to develop under the solid land. When the solid land above eventually collapses, the hole that's been sitting there is exposed and whatever was lying on top of it collapses inside.Most sinkholes form so slowly you can hardly notice them as the ground above caves in alongside the eroding surface below…then there's the other kind. The kind you hear about on the news. The big fuck-off kind that swallows cars, houses, and people. This type of sinkhole slowly develops unnoticed underground, deeper and deeper while the visible ground above remains undisturbed. Here's hoping there's no 75-foot-deep cavern sitting below the ground you're currently resting on. 2. The gympie-gympie en.wikipedia.org Plants are completely harmless, right? Sure, there are species that can cause you mild discomfort or pain, and eating some varieties is a definite no-no, but as long as you keep your mouth closed, you're pretty much safe from any real harm. Wrong. Meet the gympie-gympie, the plant that can make people vomit in pain, simply from touch. Nicknamed "the suicide plant" and native to – you guessed it – Australia, this is one piece of vegetation you don't want to encounter in a dark alley. Scientist and gympie-gympie victim Dr Marina Hurley described the pain as feeling like "being burnt with hot acid and electrocuted at the same time". Nice. At least the pain doesn't last for too long, I guess – oh wait, it last for AGES. Ernie Rider, another person terrorised by the plant, said the pain lasted for TWO YEARS and recurred every time he took a shower. Australia: where even the plants will fuck you up. 3. Fatal familial insomnia Fpg / Getty Images Ever had one of those nights where you just couldn't get to sleep? The kind of night where you spend hours staring at the clock, counting down the remaining hours you have left to sleep before needing to wake up the next morning. Maybe in your desperation you resorted to the age-old method of counting sheep, but even that let you down. No matter what you tried, sleep continued to elude you. It was hell. Prepare to feel embarrassment for your own self-pity, because things could be much, much worse. Say hello to your new worst nightmare, kind of: fatal familial insomnia. Caused by a genetic mutation, this eventual killer is a rare progressive neurodegenerative disorder that usually shows no sign until the person reaches their forties, at which point the first symptoms kick in. First the insomnia starts, with increasing brutality; then come the hallucinations, complete with panic attacks; eventually sleep becomes impossible and the victim starts to rapidly lose weight; and finally, the patient becomes mute and unresponsive. Death follows. 4. Spring-loaded folded beds Twitter: @joemols Here's the scene: You're lying in bed, and after a couple of minutes of tossing and turning you finally find that resting position in which you're perfectly comfortable. You close your eyes and feel the sweet tranquillity of sleep begin to envelop your body. Just as you drift off you're awoken by a sudden jolt. You can feel your body contorted in a strange position but you can't move it. You open your eyes, only to be met by darkness. After the panic dies down you come to the realisation that the folded bed you were sleeping on is the culprit of your painful predicament. "No worries, I can easily get out of this," you think to yourself. It takes a couple of hours of fruitless effort for you to come to terms with your fate. You're trapped until someone finds you. This scenario, which feels like a scene from a Final Destination movie, is probably more common than you'd think. A 73-year-old from Malaga, Spain, suffered a similar fate when her foldaway bed sprung up, trapping her between the bed and the wall. Sudden deaths are a thing too. A suit alleges that a man from Staten Island, New York, died instantly when a fold-up bed unexpectedly sprung up, snapping his spine in the process. Why is it the ones we love that end up hurting us most? 5. Limnic eruption en.wikipedia.org When you think of natural disasters, volcanoes, earthquakes, and hurricanes are probably the first ones that spring to mind. To be fair, they're all pretty good agents of destruction: Volcanoes are all hot and angry, earthquakes are shaky and sad, and hurricanes are just really, really windy. However there's one form of natural disaster that really doesn't get enough recognition: limnic eruptions. Sure, there's no fiery eruption of red liquid, it didn't make a name for itself in San Francisco at the beginning of the 20th century, and there certainly isn't a terrible movie starring George Clooney as a commercial fisherman trapped in one. But the reason for its lack of mainstream exposure is what makes it so terrifying: It's an invisible killer. Well, except for the corpses that lie in its wake. Let's get all scientific. A limnic eruption occurs when dissolved carbon dioxide erupts from deep lake water, spreading a deadly gaseous cloud around the surrounding area. One such instance took place in 1986, when 1.6 million of tons of CO2 suddenly arose from Cameroon's Lake Nyos. Over 1,800 people died in the disaster. 6. Waking up during surgery Christopher Furlong / Getty Images Imagine waking up on an operating table mid-operation. Take a few seconds and really imagine it. The smell. The sound. The feeling of multiple bodies hovering over as you lie semiconscious on that padded-steel work surface. You can't move to raise the alarm of those around you. You're trapped in your own body, fully aware as surgeons continue to operate, unaware that the person beneath them lies silently awake, screaming on the inside for help.Yes, this is a thing that actually happens. Anaesthesia awareness, to give it its proper name, occurs when a patient hasn't been given enough general anaesthetic and regains consciousness before the end of their surgery. Luckily the odds of this happening are pretty low – a study published in the journal Anaesthesia in 2014 found that it only occurs in 1 out of every 19,600 UK patients to go under the knife. Still, let's put those odds into perspective. Your chances of winning the lottery stand at around 1 in 45 million, and the odds of getting struck by lightning in any given year are 1 in 700,000. Damn. 7. Brain-eating amoeba en.wikipedia.org Your brain is a pretty important part of your body, all things considered. It's the organ that allows you to think, recognises objects, and reminds you of that embarrassing thing that happened five years ago. The brain is just great. If something were to happen to your brain, the results could be pretty catastrophic...so it would be a shame if there was something out there slowly devoured the brain, one teeny, tiny bit at the time. Naegleria fowleri, as it's known to people in lab coats, is a free-living amoeba found in warm rivers, lakes, and hot springs. The single-cell organism typically finds its way to the brain by taking a trip up the nose – most often when the unsuspecting victim is having a swim. In its new home, the unwelcome guest goes quickly to work, causing its unlucky owner to experience headaches, nausea, fever, and vomiting. Most cases go undiagnosed, and after falling into a coma the victim eventually dies. The reason it's often not diagnosed is actually kind of a blessing: Human infection is incredibly rare. But if you are still nervous about catching this brain-hungry amoeba, the US Centers for Disease Control and Prevention recommend using a nose clip when swimming under water.