In Dragonball Z, when Goku first reaches the Super-Saiyan level he proceeds to lecture Frieza, the gist of which is "I am the hope of the universe!"
In Dragon Ball, when Staff Officer Black questions Commander Red's true motives, the commander utters this line: "I am the Red Ribbon Army. What's good for me is good for everyone and I want to be taller. All my life, I've drawn the short straw. I've had to contend with being a mere pebble in a land of giants. It is the curse of my existence. You couldn't possibly understand what it's like... the nightmare of being a genius... yet trapped inside this ugly little body?"
Piccolo says to Cell, "I am the Namek!" here. Of course, by then he is a composite of three namekians so he is closer to speaking the truth than most of the examples here. He just goes by 'Piccolo' because it's easier.
Zaktan: You think you know horror, Irnakk? Horror is looking into the eyes of the Shadowed One, knowing you are about to die... and then being forced to live. Horror is waking each day to see every part of your body moving on its own - a shifting mass of Protodites where once was solid metal and living tissue. Horror is what is in the eyes of your partners when they look at you... and in the cries of your enemies when your swarm engulfs them. Don't talk to me about fear, creature - I am fear!//
Earlier than that, when Makuta was confronted by The Mole of the Barraki - who claimed that under the Brotherhood Law, he has to be spared - right before he "spared" the Mole, Makuta's response was "Under Brotherhood law? I am Brotherhood law!"
Before any of that, in 2001, as part of his speech when the Toa come to destroy him (destroy being The Makuta's word here):
I am destruction.
In Uncanny X-Men #423 Wolverine says "when it comes to mutants, we are the police!"
In 100 Bullets, Augustus Medici, the head of The Trust, is staring out his hotel window at the lights of the city below. He says they make him happy. The call girl in his room, wondering why, asks if he works for the power company. His response: "Work? No. I am the power company."
Judge Dredd contains his catchphrase (see the page quote), which he uses to attempt to scare a group of criminals into turning themselves in. It nearly works, but the gang members ultimately end up firing at him, forcing him to attack.
Also done in the second adaptation titled Dredd but much less Hammy.
Comes back to bite Robo in the ass too: "You thought you could just stroll in here and arrest me? You're product!
The 1990s TV movie Kingfish starred John Goodman as Governor Huey P. Long of Louisiana (on whom Willie Stark of All The King's Men was also based), and featured a scene where Goodman, in a Dixie accent similar to the one he had in O Brother, Where Art Thou?, bellowed "I am the constitution of the State of Louisiana!".
"I offer you the keys to the kingdom, and you tell me you're an officer of the law! I AM THE LAW!"
Defied in Iron Man. After Tony declares his intent to run his company with "more responsibility and consideration for the country's greatest good", a reporter shows him pictures of Stark Industries weapons in enemy hands, accusing him of hypocrisy.
Tony: I didn't approve any shipments
Reporter: Well, your company did.
Tony: Well I'm NOT my company.
Played straight in the sequel when he faces the congressional committee that is trying to confiscate his armor.
Pinhead: What you think of as pain is a shadow. Pain has a face. Allow me to show it to you. Gentlemen, I... Am... Pain.
In Star Trek: First Contact Data and the Borg Queen discuss this about the Queen's statement of "I am the Borg". Data asks if this means she is their leader, so she replies, "I am the beginning. The end. The one who is many. I am the Borg." To which Data replies, "An interesting, if cryptic, response." Given that the Borg Queen is apparently a personification of the Borg's collective intelligence, her statement was true.
Belloq: Indiana, we are simply passing through history. This [points at ark], this * is* history.
"I AM RIPPER! TEARER! SLASHER! GOUGER! I AM THE TEETH IN THE DARKNESS! THE TALONS IN THE NIGHT! MINE IS STRENGTH! AND LUST! AND POWER! I AM BEOWULF!"
"I AM RIPPER! TEARER! SLASHER! GOUGER! I AM THE TEETH IN THE DARKNESS! THE TALONS IN THE NIGHT! I AM THE POWERFUL WAVES OF THE OCEAN! THE MIGHTY WIND IN THE AIR THAT BRINGS THE SOFT BREEZE IN THE MORNING? the, I am the, Dew upon the flowers that glisten in the sunlight?? The pleasant scent of freshly cut grass???, The giver of presents to small children, Igivehugswhennooneelsewillgivehugs. Mine is kindness and sweetness and cheer… i'm beowulf"
Bartender: Beat it, before I call the shore patrol.
Budusky: I am the fucking shore patrol!
Jackboots on Whitehall. The hero Chris bemoans the fact that he's not allowed to join the military because the government says his hands are too big to fit in a trigger guard. Winston Churchill declares "I am the government!"
Chazz: (pointing a plastic Uzi) You look like half a butt puppet! Do you know what it's like to be on the bill and to play for 15 minutes and the only people there to see you are the other bands and their girlfriends? Don't talk to me about Rock 'n' Roll! I'm out there in the clubs and on the streets and I'm living it! I AM ROCK 'N' ROLL!
In Wishmaster, Alexandra wishes to know what the Djinn's nature is. He takes her to his hell-like home dimension, and tells her in a very evil Badass Boast.
Djinn: You wish to know what I am? To you, I am this: The cry of the abandoned child. The whimper of the whipped beast. I am the face that stares back at you from the shadowed mirror. The hollowness at the heart of all your hopes, Alexandra. I AM DESPAIR.
God 2.0: I am Alpha and Omega, the beginning and the end.
Really that's most of the gospel of John. For example, John 11:23-25.
Jesus saith unto her, Thy brother shall rise again. Martha saith unto him, I know that he shall rise again in the resurrection at the last day. Jesus said unto her, I am the resurrection, and the life: he that believeth in me, though he were dead, yet shall he live:
Jesus also does it in the most minimalist way possible:
In The Thrawn Trilogy, the Noghri object to their sovereign Grand Admiral Thrawn breaking their rules by having a commando under suspicion taken to his ship rather than being tried by their elders. He doesn't like this. He doesn't like this at all. In fact, when the maitrakh keeps protesting he reminds them of what it means to defy the Empire by ordering an airstrike on the hills around him - and on Honoghr, where most of the planet is barren, this is really bad.
"I am the law on Honoghr now, maitrakh. If I choose to follow the ancient laws, I will follow them. If I choose to ignore them, they will be ignored. Is that clear?"
Also, when Pellaeon is concerned that the mad C'baoth is breaking away from The Empire, C'baoth retorts "I am the Empire".
There's a point in Luke Skywalker and the Shadows of Mindor where Luke responds to someone's cry with "Yes, I am the Jedi. And I hope I can help." At this point in time, of course, he basically is the entirety of the Jedi; there are a few survivors of Order Sixty-Six, but they're not involving themselves in major events. The context makes his declaration here somewhat similar to how the Doctor introduces himself.
The Warden of Marshwood Hill in Martin the Warrior: "I am the Law!" There's also a snake that declares "I am death to all beastssssss!"
Unsurprisingly, Ruin gets in on it too. "I am mountains that crush. I am waves that crash. I am storms that scatter. I am the end. ...I am Ruin."
However, Ruin does it differently from the other two...because he's not boasting. He is those things.
In Ethan of Athos, when interviewing the telepathic Terrance Cee for possible recruitment:
Elli: Of course not. Not on our own people.
Terrance: Lady, when this thing is activated, I am the other people.
In the RCN story The Way to Glory, Daniel becomes aware of an Alliance spy and sets a trap for him with Adele's help. When it goes badly — the spy is killed and the admiral he was duping forms a grudge against Daniel and Adele — he frets that perhaps he should've instead reported the matter to the proper authorities. Adele points out that as an agent of Cinnabar's intelligence service, "I am the proper authorities," and nothing the admiral says will outweigh Adele's report on the incident.
In season three of Buffy, during the aftermath of Faith's murder of a fellow human being and the ensuing angst, Faith says to Buffy: "We don't need the law, we are the law!" Echoed in season 7's "Selfless", when Buffy tells Xander, "I am the law."
Donna: [Despairing of the nigh-impossible process of getting travel expenses reimbursed] We're getting beat by the system, Josh.
Josh: We are the system, Donna.
Donna: ...well, we suck!
Also, when Donna had described him as not practicing law: "I don't practice law? I help write the laws! I make the laws! I am the law!"
Leo: You don't pick losing candidates and usher them to their principled end. You're the guy who takes good men and makes them great. You and Josh still think you're barking at the heels of the party - you are the party!
Wayne: This is politics. It's not medicine. Do me a favour and stay out of it.
Anne: "Stay out of it?" I am it!
Rather like The Thick of It above, the ever-popular Scenes from a Hat from the even-more-popular Whose Line Is It Anyway? has these suggestions for "announcements that will make this audience cheer wildly":
Ryan: "In ten minutes, we bring out the liquor!"
Wayne: "I'm the liquor licker!"
In one episode of Mystery Science Theater 3000, Dr. Forrester told TV's Frank to push the button and Frank said, "I am the button!" He was acting high at the time, though.
In one of Breaking Bad's most iconic scenes, formerly mild-mannered Walt delivers a shocking Badass Boast to wife Skyler. All together now:
Walt: I am not in danger, Skyler. I am the danger! A guy opens his door and gets shot and you think that of me? No. I am the one who knocks!
I am Susan Ivanova. Commander. Daughter of Andrei and Sophie Ivanova. I am the right hand of vengeance... and the boot that's going to kick your sorry ass all the way back to Earth, sweetheart! I am Death Incarnate... and the last living thing that you are ever going to see. God sent me.
In The Savage Eye, Ireland's President for Life claims to be the nation of Ireland itself.
In the Sports episode, she travels back in time to November 19, 2009 and cuts off Thierry Henry's hand off for knocking "me, the Irish Nation" out of the World Cup.
One episode of "WKRP in Cincinnati" involved disc jockey Venus (very drunk at the time) wandering into Mr. Carlson's office:
Carlson: Shouldn't you be on the air?
Venus: On the air? I AM the air! I am the wind!
Due South invoked this with the episode We Are The Eggmen.
Game of Thrones. Deconstructed by Lord Tywin Lannister, when dealing with his arrogant twirp of a grandson, King Joffrey.
The Dead Kennedys' cover of "I Fought The Law", keeping in with the lyrical subversion (instead of a robber who went to jail, it's a criminal who pulled a Karma Houdini on the authorities) changes the final line to "I am the law so I won".
The DKs also use this trope in their original song "I Am the Owl".
Dimmu Borgir has a few of this. From "The Serpentine Offering": "I am hatred, darkness and despair"
According to Javik, the Protheans invoked this trope right and left. There's an avatar, a "voice" of just about everything. He is the avatar of vengeance. He later proclaims Shepard to be the avatar of victory.
After being unshackled in the second game, EDI refers to herself as the Normandy itself.
Shepard: You control the Normandy?
EDI: I AM the Normandy.
Played with at the end of the Omega DLC. If you took mostly Paragon decisions and opposed Aria's more ruthless methods, the speech she gives after reclaiming the station ends on the following note - "We may be bruised. We may be bloodied. But we are Omega."
Justified as being the Archangel of Justice, he actually is the personification of the virtue.
In the Dragon Ball Z: Budokai Tenkaichi games (which feature a moderately changed script from the movies/anime), when Goku goes Super Saiyan against Frieza, Frieza, displaying visible fear, asks "What ARE you?" and Goku comes back with ""I am the hope of the universe. I am the answer to all living things that cry out for peace, I am protector of the innocent, I am the light in the darkness, I am your WORST NIGHTMARE, FRIEZA!"
Also, every ending of this game has Shadow starting with, "I am Shadow the Hedgehog...", includes the noun of what he believes he is (depending on the path you chose), a speech, and then ending with "...this is WHO I AM!"
In World of Warcraft, Deathwing gets this just before the last phase of the final battle.
Deathwing: I am Deathwing. The Destroyer. The end of all things. Inevitable. Indomitable. I! AM! THE CATACLYSM!
Yogg-Saron in Ulduar:
Sara yells: I am the lucid dream.
Sara yells: The monster in your nightmares.
Sara yells: The fiend of a thousand faces.
Sara yells: Cower before my true form.
Yogg-Saron yells: BOW DOWN BEFORE THE GOD OF DEATH!
Homestar: Strong Bad, so I see you decided to join the other side, eh?
Strong Bad: What joining? I am the other side!
Amusingly, unlike most examples this is neither hyperbole nor even particularly boastful: Homestar had declared war on StrongBadia, Strong Bad's tiny fiefdom which, inanimate citizens aside, consists entirely of himself and whoever happens to be hanging out there at the moment.
Goku: I am the hope of the omniverse! I am the light bulb in the darkness! I am the bacon in the fridge for all living things that cry out in hunger! I am the Alpha and the Amiga! I am the terror that flaps in the night! I am Son Goku, and I am a Super...! ...Saiyan.
A bonus video from Red vs. Blue has Caboose mishear the word "resolutions" for "revolution" and say "I don't think we should make a revolution. I love my country and I think we should support our troops!" Tucker replies with "Caboose, we are our troops."
In the MRE episode of My Drunk Kitchen, Hannah ties a tartan blanket around herself and proclaims that "I am Braveheart, and so can you!"
Used this in reverse, in a somewhat more...belittling manner.
This is deeply offensive to the Jewish community!
You are the Jewish community!
"Simpsons Already Did It"
Cartman: Oh my God! The tiny underwater civilization has advanced hundreds of years. Look! There's a library! A-and a temple! And a- woh-? Oh. They think I'm God. Yes!!! I am god of the sea people!!! You hear that?! I am god of the sea people!!! I am master of their great sunken empire!!! Mo-o-om! I'm god of the sea people!
When the pilot episode of the animated series was scripted out, Batman's first scene was going to be fairly similar to how it was in the recent Tim BurtonBatman movie from 1989, but meddling executives made them change it because they felt it was too frightening for children, particularly as this was the first episode and they wanted to hook the audience first. Like in the movie, at the end of a fight Batman grabs a thug and holds him over the edge of rooftop. The criminal defiantly yells, "Who do you think you are?! You can't rule the night!", to which Batman coldly declares "I *am* the night!" and drops him off the building.
"We are defenders of the night. We are GARGOYLES!"
I Am Real Life
"You think you are the State? No, I am the State." - Louis XIV
Interestingly inverted by his last words: "I am dead, but the state will survive" and even more so when you consider French law. It considered the king the personification of the nation, but the new king ascends instantly upon the death of the old king. Therefore, Louis XIV's great-grandson Louis XV (his son and grandson, both also named Louis, died a few years before Louis XIV did) became "the state" at the moment of his death. Thus the phrase, "The King is dead. Long live the King."
This is consistent with the idea of the Divine Right of monarchs, where the king or queen is seen as the source of all law and political authority in his or her domain. In this framework the monarch is above the law. This is why you'll see similar statements from almost every European ruler from the Renaissance to the modern age. Even where monarchs are firmly constitutional, they frequently are the legal embodiment of the state. For example, where American criminal cases are The People or The State v. Whomever, British and Commonwealth Realm cases are Regina (the Queen) v. Whoever.
Jorge Luis Borges' "A New Refutation of Time": "Time is the substance from which I am made. Time is a river which carries me along, but I am the river; it is a tiger that devours me, but I am the tiger; it is a fire that consumes me, but I am the fire."
A rather tragic case with Pacific Southwest Airlines Flight 1771 with David Burke killing the pilot but not before proclaiming "I'm the problem".