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)