Imagine what a simple promise can do...

...it placed Sam on top of Doom.

Sam: I made a promise, Mr Frodo. A promise. "Don't you leave him Samwise Gamgee." And I don't mean to. I don't mean to.

And the rest of my favorites lines from The Fellowship of the Ring (the movie)

Sam: If I take one more step, it'll be the farthest away from home I've ever been.
Frodo: Come on, Sam. Remember what Bilbo used to say: "It's a dangerous business, Frodo, going out your door. You step onto the road, and if you don't keep your feet, there's no knowing where you might be swept off to."

Gandalf: All we have to decide is what to do with the time that is given to us.

Boromir: [holding the ring after Frodo has lost it] It is a strange fate that we should suffer so much fear and doubt over so small a thing. Such a little thing.

Gandalf: You cannot pass! I am a servant of the Secret Fire, wielder of the Flame of Anor. The dark fire will not avail you, Flame of Udun! Go back to the shadow. You shall not pass!

Galadriel: Even the smallest person can change the course of the future.

Boromir: I would have followed you, my brother... my captain... my king.

...and of course, Pippin moments!

Pippin: What's that?
Merry: This, my friend, is a pint.
Pippin: It comes in pints?... I'm getting one.

Aragorn: Gentlemen, we do not stop till nightfall.
Pippin: What about breakfast?
Aragorn: You've already had it.
Pippin: We've had one, yes. What about second breakfast?

Legolas: Lembas! ...One small bite is enough to fill the stomach of a grown man! [Legolas leaves]
Merry: [to Pippin] How many did you eat?
Pippin: Four.