Only got to read the Singularity bit, but while the endings were interesting, I'm not sure I feel they were well done. What dulled their effectiveness for me was that three such wildly different conclusions come about from ONE decision made in the closing minutes of the game. It's not like Fallout or even Marvel Ultimate Alliance, where it's the choices you make throughout the game that determine the ending.
It's just strange to see "moral" endings in a game where there are no moral choices to be made until the very end. You can't really play the game as a nice guy or a jerk. All your missions are the same, and you don't get to deviate to help the old lady cross the street or drive over her. So the endings are cinematic, about some character who isn't "you"; you don't feel like you've really influenced or "deserved" the ending you got, aside from that one big decision at the end.
No doubt this wasn't the first game to do this, and I'm sure I've even played other games where this happened, but Singularity is the most recent, and the only one I can recall right now.