Basically any of the deaths in Dead Space. But I was able to appreciate them because they gave an extra motivation to not die, other than being set back 5 minutes. Particularly gruesome ones included the crazy doctor's annoying regenerating pet who carefully cut off all your arms and legs after skewering you, and the final boss' picking his teeth with your arms and legs. I was also freaked out by SPOILER ALERT: Lawrence Fishburne's death to the giant rhinoceros, complete with parts of his body getting splattered across the other side of the barrier as he screams and claws at the blood smeared glass in vain.
Also from dead space, the part where you have to go on the outside of the ship inside the micrometeorite field! Fuck, it took me ages to figure out how to do that, and every time I'd just see my character get pelted apart by marbles.