tyraarane: Quicktime events. Or, in the words of Yahtzee, "press X to not die."
Sometimes they can be okay.
Sometimes. But lately they've infested cutscenes everywhere, and often have a ludicrously short timer, so missing your button presses because you thought a cutscene was a safe time to take your hands off the keyboard and eat some chips or something means instant failure and death.
You don't see them very often in PC games, or at least you didn't used to, but they pop up in console games (and thus their to-PC ports) all the time. For a particularly egregious example see
Resident Evil 5.
Actually, I meant more along the lines of, "OH CRAP, the floor just dropped in front of me! JUMP! DODGE! STOPPPP!"
The only instance of that the game ever really had was the run down into the prison, which sadly suffered from just being repeated things you had to do over and over. Needed a surprise in there, lull you into a pattern and then break it.