In no order, my favorite three are:

• That large water filled room later in the game with the white-plastered enemies that aren't there when you walk in but appear when you turn around and are gone again when you look away and then back again.
• The Andrew Ryan scene
• Sander Cohen walking down the stairs after the completion of his fetch quest and me not blowing his fat head off some oddly compelling reason.

The Andrew Ryan scene, by far

The Andrew Ryan scene is the best part by far.
But I also like the fight where Sander Cohen gets grumpy and makes you fight off a horde of slicers to classical music. Really sums up the Rapture experience, particularly Cohen's little fiefdom, of fighting over the ruins of a civilization.

The whole opening scene starting in the plane and working your way into Rapture is amazing. The monologue, the art style, the water effects all make it a very immersive experience.

The climax leading to the Andrew Ryan scene, closely followed by the plastic surgeon guy who went nuts (forgot name)

Defiantly the Andrew Ryan scene.  One of the best scenes in gaming.

Killing Andrew Ryan with a Golf Club

I would not say its one of the best scenes in gaming FEANOR

Seeing Dr. Suchong impaled on a Big Daddy drill. I hated him ever since the puppy incident ='(

spoiler....
for me, it was the video montage of all the "would you kindly" sound clips.

The descent into Rapture is amazing but my favorite is probably when you first get the shotgun and all the lights turn off and splicers come at you from everyside.

I wish I could just point to the whole Fort Frolic level, because it's amazing. But my favorite moment is probably the initial descent into Bioshock, but man the whole thing is just incredible.

The Ryan scene, with the golf club.

All the Cohen segments.

Revealing the would you kindly thing

"when you first get the shotgun and all the lights turn off and splicers come at you from everyside.
"

The descent into Rapture, and the would you kindly part.

You guys mentioned many of the best. The Ryan scene was a definite standout moment. I particularly liked the escape from Ryan's office, when the Little Sisters help you get away through the ductwork. The moments in what's-her-names hideaway with all the Little Sisters made me smile. I've played both routes through the game, but my first time I was saving all the girls, and their reactions in the hideaway gave me chills.

What a great game, now I want to take it for another spin.

my favorite scene is where your running down the hall to "Atlas's family" and the submarine explodes. but my favorite part in the game would have to be when you can't control your plasmids

actually, entering sander cohen's domain was a breathtaking experience for me. throughout the game you've witnessed just how f'ed the citizens of rapture are--but somehow healone manages to up the ante. you admire him for his artistic drive, yet feel disgusted on how he creates his work.

such an awesome character!!

"The whole opening scene starting in the plane and working your way into Rapture is amazing. The monologue, the art style, the water effects all make it a very immersive experience."

Would you kindly scene

I like the andrew ryan scene, the scene when you are first entering in the bathysphere, the room, and the view out of the windows in tenenbaums apartment, and when you are first walking into the haephaestus (before you enter, looking at the building from the outside)

There were so many memorable moments in the game, but the whole introduction to rapture and the andrew ryan scenes were my absolute favorites.

opening scene when it shows the city for the 1st time

killing the splicers while listening to swain lake ,  the would you kindly part , and shooting bees out of your arms.

"You said you would make me look beautiful! Look at me now! Look at me!"- Plastic surgery gone wrong first hand witness.

"spoiler....
for me, it was the video montage of all the "would you kindly" sound clips.
"

The Andrew Ryan scene definitely but I also liked the Sander cohen seen when he revealed himself.  Very overproduced.

"Defiantly the Andrew Ryan scene.  One of the best scenes in gaming.
"

Just like most people... the Ryan scene was awesome

1: Ryan golf club scene.

2: The opening scene with the crashed plane and the ocean..... plodding up the stairs.... doors swing open.... amazing. 

3: Everything Cohen.

Golf Club scene

EVERYTHING!!!

Andrew Ryan scene for sure, it was probably the best videogame cut scene I've ever seen. Also when the mad doctor Stenhower(sp?) was in the room that you eventuallly kill him in, and he goes on about how none of his patients are perfect, that was good.

I'M SANDER FUCKING COHEN!

Heh, I love that game.

For me it was when you catch up with Dr. Steinmen in his operating theatre. Goes to show how much of an utter whack job he is.  Also finally getting to hear a real Irish accent in a video game or in any world wide popular medium for that matter. You see we don't all sound like the Lucky Charms Leperchaun.

When everyone dies. I don't actually know if that happens, but I just wanted to add to the spoilers.

Obviously, the Ryan scene.  I hate to conform, but it freaking rocked.  :P  I also loved the moment with the guy you take corpse photographs for, after you finish his "masterpiece" and he comes down the stairs.  I also busted out laughing when I found out that there was an achievement for taking a picture of his corpse.  XD

When Ryan explains everything , ending good or when you figure out your going to be a big daddy

The whole damn game... amazing.

deleted

1: the revelation room with all the information about your past

2: fighting cohen's minions to tchaikovsky

The moment you walk into Ryan's office through when you find out who Atlas is are probably my favorite five minutes. Everything from the audio diaries to the Ryan scene, then the escape with Fontaine teasing you was great. I loved Fort Frolic, too. It seemed like the most normal thing in this strange underwater city - a mall.

In the hallway right before Ryan's office, when you see the giant board on the wall covered in little scraps of paper, with "WOULD YOU KINDLY?" written in blood on the board.

That whole part of Bioshock gives me chills every time I think about it.

A Man Chooses.............
A Slave Obeys..........

OBEY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

= D

The Ryan scene was epic, if only because it wasn't telegraphed from a mile away like another big plot twist. 

*Cough*Atlas*Cough*.

This one

Andrew Ryan / Atlas speech scene. A man chooses, a slave obeys!

the Whole Ryan scene was amazing and reminded me of the final scene in There Will Be Blood with the...............


""""""""SPOILERS"""""""""





..................Bowling Ball


Awkward Death by Awkward object



"""""""""""SPOILERS END""""""""""""


Amazing Game.

When Atlas revealed himself. I really thought he was a good guy.