"...We do all of our science from scratch..." That means Aperture Science rediscovered all of science from scratch, Fire, to the wheel, to electricity, to nuclear physics, to Artificial Intelligence that run on less power than it takes to power a lightbulb, all in about 30 years.
Chell's awesome portal ninja skills in this trailer. You wish you could be that cool in-game. It just goes to show why Chell survived all those tests in the first place.
Seeing the old test areas for the first time. They are big.
The very last move the player makes in Portal 2's single-player campaign is extremely awesome. Wheatley has learned from GlaDOS's mistakes, and at the end of the battle, you trigger the booby trap he set by the stalemate button. Somehow, Chell remains conscious long enough to see a piece of ceiling fall away, revealing a very large full moon. So what does Chell do? She portals the fucking moon! This creates a massive vacuum, sucking Wheatley into space.
Even better because Cave Johnson foreshadowed this when he mentioned Conversion Gel is made of moon rocks, which are astonishingly good at holding portals.
Made even more awesome because Valve, according to the commentary, refused to let that scene fall victim to Reality Is Unrealistic and found a way to sell the final shot taking exactly 1.4 seconds to arrive at its destination, which is the time it takes light to reach the Moonnote Actually, the Portal Gun's projectile moves at a blinding fast but still humanly visible speed— IE not remotely c— but ah well... Not like you'd catch that until you get to the fridge for a post-game snack.
Not to mention the fact that Chell, by being stubborn, relentless, resourceful, and above all, dangerous, actually makes GlaDOS give up and stop trying to kill her, despite having regained complete control of the facility and gotten rid of Wheatley.
She's so friggin' stubborn that she beats a computer in a game of mental tug of war and patience. GLaDOS simply runs out of patience and decides 'aw, screw it' and lets her go instead of spending more years, more resources, and risking further run-ins with some of the worst fates that have ever befallen any computer trying to kill a single, lone human. And if the Combine are out there, God Help Them if they dare try to kill Chell.
One should remember that GLaDOS could've killed her twice. By abandoning her on the moon, or later by simply killing her while she was asleep. but by that point she's proven so resourceful, so capable, that GLaDOS decides to give her what she wants.
Wheatley, towards the end of the game, manages to trick both the player and GLaDOS. He keeps telling the player than in a few test chambers he'll give you a surprise worth "dying for". He then tells you he'll "surprise" you in two more. You enter the first one after that, and see a faith plate indicating a jump to another level. You go to jump on the faith plate and Wheatley catapults you sideways. Even GLaDOS admits it was good.
Wheatley:Surprise! We're doing it now! GLaDOS:Okay. Credit where it's due. For a little idiot built specifically to come up with stupid, unworkable plans, that was a pretty well-laid trap.
Wheatley does it earlier by hacking into GLaDOS's test chamber in the middle of a test, rescuing Chell, and promptly leading her through the backstage areas of Aperture. Even a purpose-built idiot can have a moment of brilliance.
When fighting the midway boss GLaDOS, and the mood changes from "oh shit, how did I fall for that trap, now I'm screwed", to a smug grin when she calls in the turrets, and you know that you JUST sabotaged the turrets, THEN she calls on her precious deadly neurotoxin, which you also sabotaged, and Wheatley arrives.
Doubles up as a CMoA for Valve, managing to change the mood again, from smug grins to "oh crap, what have I DONE!?"
Wheatley:Let go! Let go! I'm still connected! I can pull myself back in! I can still fix this! GLaDOS:I already fixed it. And you are not coming back!
GLaDOS deserves an awesome label for still having the guts to insult Wheatley after she's gone through the core transfer, which from her screams must be painful as hell, and then after he turns her into a potato, she still has the guts to provoke him until he accidentally sets her and Chell free.
And later, when she attempts to shut Wheatley down with a paradox because Chell can't say it, despite the fact that doing so could kill her.
The solution to the final chamber of course 3. Timing your fall so ATLAS and P-body hit each other at the exit? The single most creative solution in the entire co-op section.
It's so awesome that despite being one of the hardest, most frustrating puzzles, beta testers insisted it be kept in the game.
Rick the Adventure Sphere, if you let him think long enough during the final battle with Wheatley, offers up a Pre-Mortem One-Liner.
Wheatley: You have been a thorn in my side long enough! Rick: Yeah, well, THIS thorn is about to take you down! ...Man, that sounded a whole lot better in my head.
GLaDOS deserves a mention during the lift to the final area. After you plug her into a mainframe outlet, she delivers a line worthy of an action movie.
Look. Even if you still think we're still enemies, we're enemies with a common interest: Revenge. You like revenge, right? Everybody likes revenge! Well, let's go get some!
What makes it all the more awesome is that it actually was Ellen McLain providing GLaDOS' voice for that project.
Really, the design of the game means that solving any puzzle or test chamber can feel like a crowning moment of awesome for the player, depending on how much trouble you find them before you solve them.
Atlas approaching the bird at the end of Peer Review. Might not sound like much at first, but as far as they know, she was a monster that could kill them easily and even gives GLaDOS a freak out moment. Yet he still gets up the courage to approach her despite P-Body's protests.
He even shows signs that he knows the birdisn't even that threatening with his first move of attempting to shoo it away.
Cave Johnson's plan to scamthe Multiverse deserves a mention for the sheer balls of it.
Some versions of Aperture Science are doing far better than others. How much better? One of them bought out Black Mesa and cancelled the test that would lead to The Resonance Cascade.Eventually at least two other Apertures manage to tap into universes made entirely of US Dollars.
"Dark Cave" produced a portal gun that works anywhere.
One Alt!Cave, who is just a freshly fired junior claims representative, sneaked into the recording room to let everyone know that Aperture's president (Doug Rattman) is embezzling funds. Even when he's not the CEO of Aperture, Cave Johnson still manages to be a total badass.
One version of Cave Johnson needs someone to break into Supermaxlantis and rescue the President. So he's bringing you in...to give a reference, because he's nominated himself.
The kickass implication that Cave-Prime isn't really Cave-Prime. How so? Upon learning about CaveDos, Prime immediately shuts down the work on GLaDOS, thus preventing the entire plot from occurring.
A Cave from a matriarchal society has managed to convince the government that he's a woman and gotten into a position of power, despite his voice at least being exactly the same.
"I'm going to attempt a manual override on this wall. Could get a bit technical! Hold on!" Then he smashes your hotel room into the wall. That's the moment realize the game is going to be pretty awesome overall.