Well, we have the thread for the worst lines, let's start one for the best. Here's mine: from "The Enterprise Incident" Romulan Commander: How could you do this to me? What are you that you could do this to me? Spock: First officer of the Enterprise. Ohhhhh Yeah
"So... I lied. I cheated. I bribed men to cover up the crimes of other men. I am an accessory to murder. But most damning of all... I think I can live with it... And if I had to do it all over again... I would."
"That's why you came to me, isn't it, Captain? Because you knew I could do those things that you weren't capable of doing? Well, it worked. And you'll get what you want: a war between the Romulans and the Dominion. And if your conscience is bothering you, you should soothe it with the knowledge that you may have just saved the entire Alpha Quadrant. And all it cost was the life of one Romulan senator, one criminal, and the self-respect of one Starfleet officer. I don't know about you, but I'd call that a bargain."
For Trek-geek squee, one moment that's always stuck with me from the DS9 premier episode: Picard: I'm sorry... have we met? Sisko: Yes, sir. We met in battle. I was on the Saratoga at Wolf Three. Five. Nine. [awkward silence] (I wasn't big into Avery Brooks at times, but the delivery of that line was spot on.) From TOS: Any part of the exchange from "This Side of Paradise" that starts with Kirk saying "Alright you mutinous, disloyal, computerized half-breed, we'll see about you deserting my ship." Or from "The Trouble With Tribbles," when the director of DS-7 accuses Captain Kirk of taking his mission lightly, and Kirk replies "No sir, I take the mission very seriously, it's you I take lightly." (Sounds dickish, but the guy deserved it.)
I'll throw in another of my favorites - from "Measure of a Man" after Picard finishes his closing statement at the hearing he walks over to Captain Louvois and says: "You wanted the chance to make law, here it is. Make it a good one". I love that, and Stewart's delivery, as always, is spot on.
Lenore Karidian to Kirk in The Conscience of the King: All this power, surging and throbbing, yet under control. Are you like that, Captain?
Kirk: "Damn it, Bones, you're a doctor. You know that pain and guilt can't be taken away with a wave of a magic wand. They're the things we carry with us, the things that make us who we are. If we lose them, we lose ourselves. I don't want my pain taken away! I need my pain!"
I don't know about best ever, but these are a few of my favorites. From TOS: The Ultimate Computer: KIRK: Genius doesn't work on an assembly line basis. Did Einstein, Kazanga, or Sitar of Vulcan produce new and revolutionary theories on a regular schedule? You can't simply say, today I will be brilliant. No matter how long it took, he came out with multitronics. The M-5. From TOS: Court Martial: COGLEY: And I repeat, I speak of rights. A machine has none. A man must. My client has the right to face his accuser, and if you do not grant him that right, you have brought us down to the level of the machine. Indeed, you have elevated that machine above us. I ask that my motion be granted, and more than that, gentlemen. In the name of humanity, fading in the shadow of the machine, I demand it. I demand it! From TNG: Darmok: PICARD: Hail the Tamarian ship. WORF: Aye, Captain. TAMARIAN [on viewscreen]: Zinda! His face black, his eyes red PICARD: Temarc! The river Temarc in winter. TAMARIAN [on viewscreen]: Darmok? PICARD: And Jalad. At Tanagra. Darmok and Jalad on the ocean. TAMARIAN [on viewscreen]: Sokath, his eyes open! PICARD: The beast at Tanagra. Uzani, his army. Shaka when the walls fell. (Picard holds up Dathon's journal, and the Tamarians beam it away) TAMARIAN [on viewscreen]: Picard and Dathon at El-Adrel. Mirab, with sails unfurled. PICARD: (holds out the dagger) Temba, his arms open. TAMARIAN [on viewscreen]: Temba at rest. PICARD: Thank you. From DS9: Trials and Tribble-ations: WORF: We do not discuss it with outsiders. From TWOK: KIRK: This is damned peculiar. ...Yellow Alert. SAAVIK: Energise defence fields. UHURA: I'm getting a voice message. They say their Chambers coil is overloading their Comm system. KIRK: Spock? SPOCK: Scanning. Their coil emissions are normal. [Reliant bridge] JOACHIM: They still haven't raised their shields. KHAN: Raise ours. JOACHIM: Their shields are going up KHAN: Lock phasers on target. JOACHIM: Locking phasers on target. [Enterprise bridge] SPOCK: They're locking phasers! KIRK: Raise shields! [Reliant bridge] KHAN: Fire! (explosions rips through the Enterprise)
"If you can't take a little bloody nose, maybe you ought to go back home and crawl under your bed. It's not safe out here. It's wondrous, with treasures to satiate desires, both subtle and gross. But it's not for the timid." -- Q I loved this...
“Could you help out a 49er, I fell down a shaft I got blown up in a tunnel. That is Unfortunate. It is most unfortunate I require large amounts of whiskey as a liniment.”
“We’ve come with some very important information. About what? About Space, about the Universe you’re preparing to enter.”
I would have to go with Garak's famous line. Bashir: What I want to know is, out of all the stories you told me which ones were true and which ones weren't? Garak: My dear doctor...they're all true. Bashir: Even the lies? Garak: Especially the lies. Also the EMH as the ECH!! The Doctor: ACTIVATE THE PHOTONIC CANNON! ^^Makes me smile every single time.
Can't believe it hasn't been mentioned yet, but, "No! No! I will not sacrifice the Enterprise. We've made too many compromises already, too many retreats. They invade our space and we fall back. They assimilate entire worlds and we fall back. Not again! The line must be drawn here! This far, no further! And I will make them pay for what they've done!" And of course, "Mister Worf... fire."