Katniss blowing up the mines around the Careers' food stash with three well-placed arrows.
Thresh killing Clove after Clove taunts Katniss about Rue's death. Bonus points for not even bothering with a weapon. Instead, simply beating Clove in the head with a rock (in the book) or slamming her into the wall (in the movie).
"YOU SAID HER NAME!"
Foxface's whole game strategy, which ends up getting her at third place, being second to last to die, without ever having to fight or kill a single person herself. This feat even impresses Katniss, who decides that Foxface was definitely the smartest of all the tributes. In fact, the only reason she died when she did was because she stole the poisonous berries Peeta had been gathering, incorrectly assuming someone who had managed to stay alive so long wouldn't risk eating berries unless they were sure they were safe to eat. In other words, whereas many tributes have died from underestimating rivals, Foxface died from overestimating a rival.
Katniss managing to bluff the Gamemakers and Take a Third Option, therefore making the 74th Hunger Games the first time in history that two tributes were allowed to live.
All of District 12 gets one early on, with their refusal to applaud Katniss volunteering to take her sister's place in the Games, described as the highest form of rebellion available to them.
To the everlasting credit of the people of District 12, not one person claps. ...Silence. Which says we do not agree. We do not condone. All of this is wrong.
"I like her! Lots of..." He can't think of the word for a while. "Spunk!" he says triumphantly. "More than you!" He releases me and starts for the front of the stage. "More than you!" he shouts, pointing directly into a camera.
Katniss' performance in her private archery session, scoring several hard bullseyes after getting the feel of the bows, and getting angry because they don't bother watching so she shoots the apple out of the mouth of the pig that the Gamemakers are eating, causing one to lose his footing with surprise and fall into a bowl of punch. She storms out and immediately thinks that the consequences of her impulsive behavior may be dire, they may even give her an immediate death sentence. They actually give her a score of 11 out of 12, making her the highest ranked before the games start.
Which was, in itself, a death sentence, as now she will be seen as a potential threat by the Careers and will therefore be a primary target.
The next year, there's a forcefield protecting the Gamemakers.
Peeta going back to find Katniss after she dropped the tracker jacker nest on him and the Careers. Not only does he risk getting stung by the deadly wasps, he blows his cover with the careers and after encouraging Katniss to run he goes one-on-one with Cato to buy her time, getting a life-threatening wound in the process.
The reason Haymitch was yelling outside of Katniss's hospital room after the Games: The gamemakers wanted to surgically alter her chest, but he wasn't having it. Might also be his only real Papa Wolf moment, too.
Peeta's announcement that he's in love with Katniss in his interview for the 74th games counts. Even in-universe, as it proves just how adept he is at manipulating the audience.
Not only was it implied that Cato managed to succeed in killing Thresh, but he actually managed to hold the muttations at bay for over an hour before he finally got overwhelmed.
Katniss blowing out the forcefield in the Arena in the climax with nothing more than an arrow, a wire, and a big bolt of lightning.
The discovery that Haymitch won the 50th Hunger Games Quarter Quell by using the arena force field as a weapon. This troper found it even better than the stint with the berries.
Added to the fact that he outlived forty-seven other tributes. When Katniss mentioned what his Quell twist was I became very impressed and intrigued, even before we find out how he did it.
Even better: he was literally holding his innards for the last moments of the Quell.
Katniss shooting so well during training that even Brutus, a Career victor who's more experienced than her in the art of killing, wanted her as an ally.
The part where Katniss goes to the Quarter Quell's interview in her wedding dress, which starts out as a Dethroning Moment of Suck until she starts spinning,setting her dress on fire and turning her wedding gown into a mockingjay dress. Of course, it's apparent to some that Cinna's as good as dead for what he just did, but it's a huge Take That to the Capitol, and the fact that he did it knowing full well what it might cost him served as an inspiration to all the rebels still on the fence because of what they stood to lose.
Peeta sets the entire Capitol afire and destroys President Snow's plans to use the Quarter Quell to bring Panem fully back under his control with six words: "if it weren't for the baby."
Really, all the victors are awesome in that series of interviews, as they remind you that, unlike most tributes, they are not scared kids dazzled by the spotlight, but hardened mentors who know exactly how to manipulate the crowd. One after the other, they talk about how sad they'll be to leave the people of the Capitol, how they wonder whether the new rules are actually legal, whether President Snow maybe doesn't understand/care/have the power to resolve the problem and so on until Peeta drops his bomb in the final interview. Basically, they turn the Quarter Quell into a spectacular own-goal for Snow, and leave his hold on the hearts and minds of Panem far weaker than it was before he changed the rules to avoid this precise situation.
Katniss, before the Quarter Quell interviews: However much President Snow may hate me, this Capitol audience in mine. The poor girl has been scared and desperate the whole book, been personally threatened by Snow, had a minor Heroic B.S.O.D. after the Quell announcement, didn't get to say goodbye to her family and friends before leaving, and is pretty sure she won't come out alive this time. But the Capitol citizens adore her and Peeta, so she isn't even nervous about the interview this year, and may even get in on the Victors' collective guilt trip about sending them back into the Games. It's the first time she seems truly confident in the book, you just want to cheer because she's basically saying, "To hell with President Snow, I got this."
"You... hung... Seneca Crane?"
"Yes. I was showing off my new knot-tying skills, and he somehow ended up at the end of the noose." Definitely one of Katniss's funniest and sharpest snarks. And it wasn't even in her inner monologue, she flat out SAID that!
Then you have Peeta's showing off his skills - painting Rue the way she appeared in flowers when Katniss gave her the closest she could get to a decent burial in the arena. The best part? He and Katniss didn't plan to be subversive together - they just both did it.
Catching Fire has an extended group one with the conspiracy to break out of the Quarter Quell.
Let's lay this one out: first, the organizer, Plutarch Heavensbee, has to become Head Gamemaker, designing both the entire arena and the equipment to facilitate the escape. He not only provided the wire, tree, and lightning storm needed to down the forcefield, he made the arena closed in enough to allow them to reach the field quickly, and provided enough fixed destruction to avoid being forced into throwing random destruction to spice things up
Then Haymitch set up a code for communicating with the tributes through bread.
Johanna managed to convince the Capitol to overlook how Heavensbee slipped in the wire for the escape
Mags ran into a cloud of blister agent to keep the alliance on track
Finnick both was generally highly competent and was the person to first meet up with Katniss
Wiress figures out the arena's theme before anyone else
Beetee designed the forcefield, figured out how to overcome it, and electrocuted himself stabbing it in order to help Katniss figure out how to overcome it without tipping off the Gamemakers, as he had to know that wouldn't work
Katniss actually took down the forcefield by shooting it with an arrow
Peeta despite having walked less than a year on his prosthetic leg and having had his heart stopped by an electric shock only hours before still manages to fight as good as the rest of them and physically carry Beetee around the arena.
The kicker? They planned and carried out the whole thing while under constant surveillance and then on live national television without tipping the capital off at any point.
Finnick revealing the dirty secrets of all the important people in the Capitol in front of the entire country. Particularly awesome since we know what he had to go through that inadvertently allowed him to get this information, so when he reveals it he is basically throwing it back in the faces of the people who abused him for years. Katniss notices the broadcast of Snow's secrets doesn't get interrupted, suggesting even the people responsible for the Capitol's official television programming were curious about those particular secrets.
Katniss assassinating the current president Coin with the arrow she was meant to use for executing the former president Snow. Not exactly a big moment in terms of what happens but the fact that she did so and wasn't killed on the spot and is ultimately let go with basically a slap on the wrist make it pretty awesome for her to get the jump on someone who caused her so much pain.
Fire is catching. And if we burn, you burn with us!
Peeta essentially cures himself from the hijacking through sheer force of will, making him the only known case of a person recovering from it.
Also, Peeta managing to warn Katniss and the rest of the people in District 13 about the impending bombing, despite the hijacking having already begun and despite knowing that he's going to be tortured for it. Just think about it.
Katniss throwing herself between the rebels and the district 2 survivors, who just crawled their way out of a collapsing mountain, in an attempt to keep them from killing each other. Katniss might think of herself as a bad person, but it's clear she really isn't.
The Hunger Games
As with the books, the aforementioned scene where she shoots the apple, but with bonus points for the line she gives afterwards:
The delivery of the line - as well as the small, mocking curtsy that goes along with it - make it even grander.
Even Haymitch, who at this point has not shown Katniss a great deal of respect, says he wishes he could have been there to see it.
When Marvel throws a spear at her, Katniss twists to the side and fires an arrow into his chest, all in the space of about a second. But then we turn to see Rue behind Katniss...
Katniss' failed rescue of Rue. Or more precisely, her Due to the Dead, which sets off a riot. She leaves Rue's body as if she is sleeping among flowers in the sunshine grasping a bouquet with mockingjays singing around her, and then salutes the camera. We're then shown District 11, where the crowd return the salute, and then turn to attack the Peacekeepers.
And the first man to attack the Peacekeepers is implied to be Rue's father.
Peeta gets one in the movie that wasn't in the book. Namely, picking Cato up and judo-throwing him off of Katniss during the fight at the end.
The Tribute's parade. Lalala, the Tributes look lovely, blahblahblah... who is that in the back?
Making it even more awesome is Peeta and Katniss holding their hands up high. "Come on, they'll love it" is right.
One of the most simply awesome moments of the film however is when Thresh in a rage kills Clove in revenge after hearing her boasting about her group killing Rue. He simply grabs her head and slams it against the wall until she stops yelling. The guy's largely a walking Offscreen Moment of Awesome, but we get to see exactly why everyone respects him.
It's just topped off by him letting Katniss go for being Rue's friend and treating her body properly.
Seneca Crane's implied Better to Die than Be Killed moment at the end with the nightlock berries. Not for Seneca himself, mind you- for President Snow, who is strongly implied to have set this up and cements himself as a Magnificent Bastard with it. Guy might be a villain, but the irony is truly delicious and you can literally see him dreaming it up.
Haymitch managing to save both his tributes by convincing Seneca Crane to calm the riots by letting the viewers focus on young love.
Then you consider hindsight. Haymitch manages to doom Seneca by suggesting that. If words could kill, then Haymitch is the first character to actually kill off a Capitol member in the entire trilogy. Although, if actions speak louder than words, Katniss managed to strike a blow to the Capitol before she and Peeta even got their hands on the Nightlocks by how she sent off Rue and inadvertently caused the riots in the first place.
Four words: "I volunteer as tribute".
Peeta throwing the weight across the room (by Katniss' insistence) to let the Careers know that he's not just another piece of easy meat. According to Word of God that thing was between 50 and 75 pounds.