Zelda - Skyward Sword
Absolutely beautifully made game, and one of several Zelda games I'd like to put on this thread.
Again, I could have most Halo games on this list.
It has to be bioshock for me. I literally sat there open mouthed for the last few hours.
Final Fantasy X, Portal 2
Kingdom Hearts Birth by sleep's secret ending.
Oh wait, it never ends!
Halo: CE was awesome, so that gets my vote.
The first time I completed Kingdom Hearts 2 was pretty damn awesome
Assassins Creed games have epic endings
Loved the ending of Splinter Cell Conviction.
"Brother. That's family, right?"
I'd have to say Mass Effect 3. I mean what better way is there to end such an amazing story then by introducing an irrelevant character within the last few minutes and choosing the colour of explosions from the Crucible :P
Honestly, I can't make my mind up on a single ending. So here's a list of the few best ones from which I can recall:-
Assassins Creed Revelations - Really, all AC games have crazy endings in one way or another and that's a good thing considering the nature of the story. However, ACR was the first to deliver a conclusion that actually felt like an end. Altair and Ezio were given the most justice in that ending imo
Mass Effect 2 - Lets forget about the 3rd game. This really was the highlight of the story. Throughout the game, the emphasis on the final suicide mission is immense. You go in really with no idea what will happen and can end up with wildly varied results depending on how you played the game.
Red Dead Redemption - This one is a no-brainer, It's also improved by the addition of the God figure character in the "I Know You" mission
MGS4 - This one is also a no-brainer, however I did find it the slight bit underwhelming when I found out Zero founded the Patriots