What movie scene can you watch over and over and never get tired of?

[JaseSF]

The end of COLOSSUS: THE FORBIN PROJECT when one character realizes it's futile to run.

Many scenes in THE OMEGA MAN. Heston driving around the abandoned city, the telephone ringing bit, Matthias's speeches and especially the scene where the Family gather together hoping to finally do in their enemy once and for all.

LOGAN'S RUN, especially anytime Jenny Agutter is on screen.

THE THING FROM ANOTHER WORLD. Never get tired of rewatching this one largely due to its likable characters.

JASON AND THE ARGONAUTS: The skeleton army at the end, Talos and the Hydra.

[BlackAngel75]

I got one more:

Near the end of Armegeddon, when the little kid  was running toward his estrained father (who was one of the astonauts/oil digger).  It always gets my eyes to water.

[LilCerberus]

Nastasja Kinski's nature walk in Cat People

Tania empties a clip into a guy who's already dead, then kicks him in the groin for good measure in Lady Terminator

The opening scene in Rumble Fish, in which Matt Dillon's character is introduced in a heroic light, only to lose a billiard game, followed by a conversation that reveals his bravado doesn't really inspire confidence

[quabrot]

Any scene in Godzilla: Final Wars with Don Frye. 

Like when he tells the aliens "There's two things you don't know about Earth.  One of them is me.  The other is Godzilla.".

Or the final confrontation where he is ready to fight Godzilla with just his katana.

[Allhallowsday]

Jase mentioned THE THING FROM ANOTHER WORLD, endlessly watchable to me... and also JASON AND THE ARGONAUTS, probably my favorite owing much to the skeleton attack. 

I'll agree with RCMerchant that TEXAS CHAINSAW MASSACRE includes a few unforgettable senes... and Flackbait with WHERE EAGLES DARE and Soylentgreen with SOYLENT GREEN (though my favorite is the superb E.G. Robinson's final scene -- a heartbreaker)
***
My quick choices for favorite scenes:

The end of YOU CAN'T TAKE IT WITH YOU (1938) when Lionel Barrymore and Edward Arnold begin to play a harmonica duet "Polly Wolly Doodle."  What a happy wonderful movie! 

OSSESSIONE (1943): director  Luchino Visconti trails a tramp off of the back of a truck, verbally disparaged for his shabbiness, into a roadside eatery and the kitchen at the back . . . a tramp whom up to that moment we see only from behind.  Clara Calamai toiling in the hot kitchen glances up and reacts with a doubletake as just then Visconti chooses to first reveal Massimo Girotti's stunning face  . . .

NIGHT OF THE HUNTER (1955) most of this is mesmerizing, particularly the fleeing children in the rowboat drifting under the spider's web, or the night hours passing in the barn with the moon rise . . . I love the scene when the youngins' get out of Robert Mitchum's clutches . . . a very beautiful and touching film. 

VIRIDIANA (1961): director Luis Bunuel has a famous scene where the low-life tramps, having invaded the main house and in the process of trashing it, recreate the vignette of DaVinci's Last Supper . . .

CARNIVAL OF SOULS (1962): many scenes in Herk Harvey's creaky classic such as Candace Hilligoss' sudden appearance on the river bank, her trips to the abandoned Saltair pavilion, the night driving sequences, all still haunt me with melancholic music (Gene Moore's music is available now on CD and well worth it!) 

Of course the finale of CASABLANCA is what "classic" was meant to look like.  And PATTON is endlessly watchable; plop me down in any scene and I'm riveted. 

[Bmeansgood]

Burt Reynolds smoking during the Rollergirl scene in Boogie Nights.

[BeyondTheGrave]

When the Coloinal Marines first face off against the Aliens in" Aliens".

The SWAT attack in the apartment in the "Dawn of the Dead"

Who beats up who in "SLC Punk"

The last concert in "Burst City"

Anything from "Return of the Living Dead or "The Thing"

That weird dance in "Night Of the Demons"

[Yaddo 42]

Count me in for the skeleton fight in Jason and the Argonauts
Any car chase in any Mad Max film.
Max vs. Blaster in Thunderdome
Teddy Bass sitting in the bank as the vault door opens in Sexy Beast
The "march" at the end of Bucakaroo Banzai
The cast credits montage/end credits in Phantom of the Paradise.
The beginning of Tom Horn, until Richard Farnsworth comes to see Horn with his face kicked in.
The long tracking shot opening of Touch of Evil.
Any random bit of Richard Lester's Musketeers films
The climatic battle in Dragons Forever
The bicycle chase in Project A
James Cagney doing anything in One, Two, Three
Anything from Point Blank
Most of Posse, especially if Bruce Dern is in a scene
Pick a scene, any scene from Blazing Saddles

[Shadow]

This scene took a lot of heat at the time, but damn it, I love it and can watch the Yoda/Count Dooku confrontation from Attack of the Clones over and over again. After all those years of thinking of him as a stiff, old puppet, Yoda unleashed some major whoop ass. I will never forget the first time I saw the film and the audience cheering as loud as possible when Yoda revealed and activated his lightsaber.

[dean]

When the Coloinal Marines first face off against the Aliens in" Aliens".

You could pretty much include all of that film for me and a few of my friends, especially since there's a lot of scenes that I can rewatch over and over in Aliens, such as when they first wake up, to eating food in the mess hall, to getting ready to land on the planet...

[RCMerchant]

 JEEZ! Hoe did I not mention the skeleton warriors?!...Lemme see...
.The Cyclops! 7th Voyage of SINBAD!
.Almost any scene in the SHINING.
.Christopher Lee and Peter Cushing duking it out in HORROR of DRACULA.
.The RAMONES doing "Do You Wanna Dance?" in the hallways of ROCK and ROLL HIGH SCHOOL!!!Hell..the whole movie!!!!
.The crazy hillbilly chasing the girl through the woods in POOR WHITE TRASH...aclassic,terrifying scene!If youve neer seen PWT,watch it for that alone!
.the Dawn of Man...2001...
 
                                        [youtube=425,350]http://www.youtube.com/watch?v=sdoA3AJ6zGE

[Allhallowsday]

.The Cyclops! 7th Voyage of SINBAD!
.Christopher Lee and Peter Cushing duking it out in HORROR of DRACULA.
.The RAMONES doing "Do You Wanna Dance?" in the hallways of ROCK and ROLL HIGH SCHOOL!!!Hell..the whole movie!!!!
.the Dawn of Man...2001...

Yes, the too-easily overlooked giant Cyclops in 7TH VOYAGE OF SINBAD (the giant bronze man in JASON & THE ARGONAUTS is another reason I love that movie.) 

It's interesting in 2001: A SPACE ODYSSEY how the film cuts from the bone tossed skyward by the ape to the bone-shaped spaceship floating before us . . . great music in that film which reminds me . . .

VERTIGO, mentioned by another poster (possibly in another thread  ) who loves VERTIGO but has seen no other Hitchcock films (! you'd think VERTIGO would be the missing one, but then again, I know somebody who hasn't seen PSYCHO) anyway, there is the scene where Judy (Kim Novak) has almost become Madeleine, but her hair's unpinned, and Jimmy Stewart insists she pin it up "like her..." Judy snorts . . . y'know as implausible as it all is, once you get that it's kind of a Frankenstein story and just symbolic it becomes fascinating.  Judy emerges from the privy into a lurid green hallo from a neon sign outside her room's window, the fantastic score by Bernard Herrmann swells (an homage to Wagner's "Tristan Und Isolde") she steps out in her spike heels, recreating a vision of Madeleine, and renders Jimmy Stewart blubbering and speechless.  Pretty cool stuff.  I do love that film and could look at it endlessly but must confess the first time I viewed it, I did not care for it much.

[RCMerchant]

Hitchcock's films all have scenes worth rewatching-!
.The children being led from the school in the BIRDS.
.Carey Grant running from the bi-plane in NORTH BY NORTHWEST
.Paul Newman stuffing some poor shmucks head in an oven in TOPAZ
.The STAIRS!!!!...VERTIGO
and...of course,the influential shower scene in PSYCHO.

[Just Plain Horse]

I'm with Allhallowsday, I can put Final Wars on an endless loop and keep watching it over and over.

Other films:

The only part I liked from the original NIGHT OF THE LIVING DEAD: "They're coming to get you, Barbara." 

The beginning narration by Raymond Burr in GODZILLA, KING OF THE MONSTERS ... some of his narration I thought was pretty decent; it's the dubbing that sucks. 

The scene in CARNIVAL OF SOULS, where Candace Hilligoss' character suddenly appears on the river bank. No explanation... there's something very primordial in her movements and the mud covering her.

The big, but brief battle in George Pal's WAR OF THE WORLDS, from the toasted preacher to the plane crash- beautiful. 

In MATANGO, when they find the wrecked ship. Even with no sound, this scene still gives you a very powerful impression of decay. 

Hitchcock's VERTIGO, the final act where Jimmy Stewart's character realizes who's been faking... and his speech as they climb up the tower, "for the last time".   

Just about any part of CAPE FEAR (the remake, with DeNiro), but the scene where he meets his lawyer in his car and takes his keys is probably my favorite. "Fourteen years since I held a set of keys."

[DistantJ]

The First Person sequence in DOOM.