One manner of death that's always been particularly horrifying to me, ever since I saw it used in a crime show, is death by falling in an active trash compactor. Especially when no one's around to shut it down.
Some time ago, I worked at a computer repair job where me and my friends were sort of the resident "yeah, they don't look like they do much, but they're really efficient" guys. We were very close to one of the neighboring department's supervisors and so we would have some harmless fun at her expense every now and then, and she'd usually brush it off and we'd have a good laugh about it.
Well, one day we were supposed to be painting some stuff with this red paint we were given, while the rest of our area continued their normal job. The supervisor didn't know this.
Well, we were walking back to the front for lunch (except for one of us, who was staying behind to put things away) and had distressed looks on our faces. The painting was aggravating, and our actual supervisor kept distracting us from the very work she gave us to do by giving us other things.
Well, we guess it was the red paint on our hands, and the look of distress, but something caused our supervisor friend to start looking anxious. We jokingly said that our friend was still back there, and there was an accident, but it was lunch and so we were going to grab our food. Yes, kinda dickish, but we said it so obviously jokingly that we thought nothing of it.
Oh no. Oh dear no.
Supervisor starts freaking right out at this point, and does so even a little after we tell her we were just joking. She screams at us a little bit, then tells us never to do it again and goes back to her area. This is the first time she's ever taken anything really seriously in the warehouse, and we didn't see her the rest of the shift.
Well, as we were leaving, she stayed outside to grab a cigarette and told us to come talk to her. Turns out, she was working a job just a few years before this and was the only person with any sort of medical training and certification. So, when a kid got trapped in a very slow moving compacter with a jammed lever, she had to be there.
She was beginning to get kinda distant, like she was watching it again, and telling us how it took an entire half hour for the compacter to do him in. 30 minutes of full contact, blood, popping, tears, and then silence. There were 3 men trying to stop the lever, but it was known around the plant that it was so roughed up, that the machine wouldn't let him go until it was done with him. Everyone but those four stared anywhere but at the machine, and she said no one could blame him. The entire plant was silent, except for his screams.
She left that job the next week, and lived with her girlfriend, jobless, for a year after that.