I have a bunch of quotes saved on my phone. Let me choose a couple... Hrnh.

"No, I'm from Iowa. I only work in outer space."
~Captain Kirk, Star Trek IV: The Voyage Home

"I'm not gonna eat it that's disgusting! I'm gonna wear it as a worm stache!"
~Misc. gag reel from Doctor Who I believe

No, I am your father!

-Star Wars Episode V

America’s one of the finest countries anyone ever stole.

Perhaps, after all, America never has been discovered. I myself would say that it had merely been detected.

Watch your thoughts, for they become words.
Watch your words, for they become actions.
Watch your actions, for they become habits.
Watch your habits, for they become character.
Watch your character, for it becomes your destiny.
and another one
there are 10 people in the world, those that understand binary and those that dont
there are 3 people in the world those that can count and those that cant
I LOVE THESE THINGS!!!

It is less of a one-line quotation and more a piece of dialogue :

"All right," said Susan, "I'm not stupid. You're saying humans need ... fantasies to make life bearable."
No. Humans need fantasy to be human. To be the place where the falling angel meet the rising ape.
"Tooth fairies? Hogfathers?"
Yes. As practice. You have to start out learning to believe the little lies.
"So we can believe the big ones?"
Yes. Justice. Duty. Mercy. That sort of thing.
"They're not the same at all!"
Really? Then take the universe and grind it down to the finest powder and sieve it through the finest sieve and then show me one atom of justice, one molecule of mercy. And yet you act, like there was some sort of rightness in the universe by which it may be judged.
"Yes. But people have got to believe that or what's the point?"
My point exactly.
- Death and Susan, Hogfather.

"Bang."-Spike Spiegal

"This is going to be legen... wait for it... dary!"-Barney Stinson

"What business do you have in a wardrobe!?"-Tamaki Suou

"You can do whatever you want, you just have to know what that is."
-Abed Nadir, Community

"Try not to suck!"
-Deadpool, Marvel vs. Capcom 3

Words to live by

Van Kleiss from Generator Rex to an Evo: I dont need you anymore. Go start a few legends. (He was in ancient Egypt)
Piccolo and Vegeta from Super Android 13:
Piccolo: Is it over yet?
Vegeta: Not until the fish jumps. *fish jumps* It is over. *credits roll*

All I can think of right now.

The fifth Doctor wore a stick of celery on his lapel, and the tenth Doctor thinks it's funny and disturbing.

"Imitation is another form of flattery."
-anonymous

"Whatever you're going to be, be a good one"

-Abraham Lincoln

"Are your cookies made with real girl scouts?"

-Wednesday Addams

Wednesday: "If I drop the baby and the bowling ball at the same time, which will land first?"
Pugsly: "The bowling ball?"
Wednesday: "Correct. But which will bounce?"

From 'Even More Brawl Taunts':
: I dont get it. They replaced me with you. What do you have that I dont?
: *While powering up that blue orb thing* Bllluuuueeeeeeeeeeeee ballzzzz.
: And?
: The Aurraa.
: And?
: *Grabs Mew* Your motherrr.
: *Ashamed*