In my most recent script, Zombie, NJ, I tried to make a certain sequence really stand out. I tried to make it a moment to remember. I could have written it pretty easily, a quick scene that gets the characters from Point A to Point B.
But I wanted it to be memorable. Like one of those sequences that you'll remember as your favorite part, sequence or whatever. It's a scene in a crawlspace, the main characters (three 15 year olds) are hiding under the house as zombies rip apart the house above, searching for fresh meat. I tried as best I could to draw out the tension (the horror above them, their current dark & wet surroundings). On the page, I made it last about 2 pages, when it could have been easily half that. It's my favorite scene in the screenplay.
In the last year, we had some fine moments in theaters:
(500) Days Of Summer - You Make My Dreams sequence.
Up In The Air - The scene where they're firing the older employee via teleconference, and he's actually in the adjoining office.
The Hurt Locker - Many moments here, but one that sticks with me is the sniper scene - Bigelow really draws out the drama here. I think the scene was like 15 minutes long, ever wrending second was amazing.
Up - The opening montage.
There are certainly others, but you get my point. When I started writing I didn't pay as much attention to these things, was simply worried about dialogue, structure, story (things we obviously need to worry about!) but after the script reader/agent/assistant/Spielberg puts the script down, you want to give them another reason to pick up the phone.