The film opens on epic, with prisoners tugging an enormous ship into a dry dock while waves crash onto them. The ship is threatening to fall over, and Javert watches from above. Then Valjean is forced to carry an enormous pillar, and actually manages to lift the thing! The lifting's done all in one take too, so it looks like he really did do it.
The end of "Valjean's Soliloquy" where he tears up his papers and is resolved to become a good man, even of the law thinks he can't change.
On a meta-level:
Anne Hathaway specifically said during the shoot of Fantine being divested of her long hair that the haircutter should cut close to the scalp, and that even if she was wounded the cutting should continue.Dyeing for Your Art? You bet.
Her performance of "I Dreamed a Dream." It's done in one take, in close-up, with nowhere for any flaws in the performance to hide. She knocked it out of the park and right into the Best Supporting Actress Oscar! Even better, nobody was particularly surprised that she won for what was basically a fairly short performance in a musical; she was so self-evidently awesome that hardly anyone had any doubt that she'd get it.
Valjean and Javert have a sword fight during "Confrontation." To be clear, Javert has a sword. Valjean breaks a piece of timber off the wall with his bare hands and uses it to parry Javert's attacks. He is disarmed but he escapes but jumping out a window like an Action Hero. How badass is that?
The lyric change has been described as "simultaneously metal and Buddhist."
It's worth noting that Gavroche is the first person in the film who actually gets the line "Vive la France". And damned if he doesn't deserve the honor.
Eponine putting on her cap as she belts out "But he never saw me there!" on "One Day More".
The first time "Do You Hear the People Sing?" is done. It's saved for the funeral procession of General Lamarque. As the casket is carried past, the students start singing it softly, then the other people join in, and then they all belt it out while climbing on the casket. It's epic.
How epic, you ask? One of the soldiers who's supposed to be guarding the hearse joins in.
Marius somehow manages to steal a horse from one of the soldiers and rides off on it carrying a huge flag, with the others running behind him.
The "Red And Black" reprise after the barricade is built.
When Javert is captured by the students, he easily throws off the men pinning his arms down, punches out two more, grabs his cane and knocks down several others before he is swarmed and taken down by sheer numbers.
Gavroche's death in the film is less tearjerker, more Defiant to the End. Part of this may have to do with the fact that this is the first time he actually sings Little People in the film, but regardless, staring the man who's about to shoot you in the face and snarling out your last words is pretty badass.
Realizing they're about to become Doomed Moral Victors, Enjolras tells his followers that anyone who wishes to leave may do so. A short pause...followed by everyone joining in a gradually building reprise of "Do You Hear the People Sing?", started by brave, loyal little Gavroche.
Just as he and Grantaire are about to be shot to death by the soldiers, Enjolras raises his fist clenching the revolutionaries' flag in a final act of defiance.
There is something both sad and heroic about the students' Last Stand, as they fight with everything they have while retreating into the cafe, doing things like knocking out the stairs and throwing bottles to buy seconds more time. "Make them pay for every man," indeed.
The throwing bottles bit actually goes into Fridge Horror territory, with the original novel stating that the bottles they threw contains vitriol, known in modern times as nitric acid.
The entire finale, and Marius and Cosette, with the ghosts of Valjean, Fantine and everyone who died at the barricade watching the Communards march during the revolution in 1870, showing that the rebellion really did succeed.
Just before the movie ends, it shows the three main actors; Hugh Jackman, Anne Hathaway and Samantha Barks.
According to an earlier version of the script, the finale was rather supposed to be the 1848 revolution, which started the Second French Republic and first Presidency. Which is a little bit Fridge Horror when you think about it — that president (Napoleon III) made himself Emperor a few years later, and exiled Victor Hugo.
Another meta-level: the medley performed at the 2013 Academy Awards, culminating in "One Day More" performed not only by the film's principal cast but also by several Les Mis alumni as the backup chorus.