"Strange women lying in ponds distributing swords is no basis for a system of government. Supreme executive power derives from a mandate from the masses, not from some farcical aquatic ceremony." — Dennis the Peasant, Monty Python and the Holy Grail
"Three rings for the Elven kings under the sky, seven for the Dwarf lords in their halls of stone, nine for the mortal men doomed to die, one for the Dark Lord on his dark throne, in the land of Mordor where the shadows lie. One ring to rule them all, one ring to find them, one ring the bring them all, and in the darkness bind them. In the land of Mordor where the shadows lie." -LOTR
"I’m sorry, Dave. I’m afraid I can’t do that." - HAL, 2001: A Space Odyssey
"Spock. This child is about to wipe out every living thing on Earth. Now, what do you suggest we do….spank it?" - Dr. McCoy, Star Trek: The Motion Picture
"With great power there must also come - great responsibility." - Amazing Fantasy #15 (August 1962)
"If you can’t take a little bloody nose, maybe you oughtta go back home and crawl under your bed. It’s not safe out here. It’s wondrous, with treaures to satiate desires both subtle and gross; but it’s not for the timid." - Q, Star Trek: The Next Generation "Q Who?"
"Five card stud, nothing wild. And the sky’s the limit" - Captain Jean Luc Picard, uttering the last line of the series, Star Trek: The Next Generation "All Good Things…"
"If you think that by threatening me you can get me to do what you want… Well, that’s where you’re right. But - and I am only saying that because I care - there’s a lot of decaffeinated brands on the market that are just as tasty as the real thing." - Chris Knight, Real Genius
"We’re all very different people. We’re not Watusi. We’re not Spartans. We’re Americans, with a capital ‘A’, huh? You know what that means? Do ya? That means that our forefathers were kicked out of every decent country in the world. We are the wretched refuse. We’re the underdog." - John Winger, Stripes
"If I’m not back in five minutes, just wait longer." - Ace Ventura, Ace ventura, Pet Detective
90 more here - Wired