Whenever you look to the stars, think of one of them as my soul. Defend this family, Autobots, as they have you. Defend all they can be. There are mysteries to the universe were never meant to solve, but who we are, and why we are here, are not among them. Those answers we carry inside. I, am Optimus Prime, and this message is to my creators: Leave planet Earth alone, because I’m coming for you!

In any war, there are calms between storms. There will be days where we lose faith. Days where allies turn against us. But the day will never come, where we forsake this planet and its people.

Fate has yielded its reward, a new world to call home. We live among its people now, hiding in plain sight, but watching over them in secret. Waiting. Protecting. I have witnessed their capacity for courage, and though we are worlds apart, like us, there’s more to them than meets the eye. I, am Optimus Prime, and I send this message to any surviving Autobots taking refuge among the stars. We are here. We are waiting.

 Nevelon wrote:

I forget which giant shark movie it was, but one of them had a classic epic speech, punctuated with the shark eating the guy giving it.

 Nevelon wrote:
Mystery Men is an underrated movie, but has a great speech from the shoveler.

I don't know who you are. I don't know what you want. If you are looking for ransom, I can tell you I don't have money. But what I do have are a very particular set of skills, skills I have acquired over a very long career. Skills that make me a nightmare for people like you. If you let my daughter go now, that'll be the end of it. I will not look for you, I will not pursue you. But if you don't, I will look for you, I will find you, and I will kill you.

'Are you ready to put down your toys and become a real race car driver!"

They used to say if man could fly, he'd have wings, but he did fly. He discovered he had to.

Do you wish that the first Apollo mission hadn't reached the moon, or that we hadn't gone on to Mars and then to the nearest star? That's like saying you wish that you still operated with scalpels and sewed your patients up with catgut like your great-great-great-great grandfather used to.

I'm in command. I could order this, but I'm not because Doctor McCoy is right in pointing out the enormous danger potential in any contact with life and intelligence as fantastically advanced as this, but I must point out that the possibilities - the potential for knowledge and advancement - is equally great.

Risk! Risk is our business. That's what this starship is all about. That's why we're aboard her.

You may dissent without prejudice.

Do I hear a negative vote?

"Just there the barbarians huddle, sheer terror gripping tight their hearts with icy fingers... knowing full well what merciless horrors they suffered at the swords and spears of 300. Yet they stare now across the plain at 10,000 Spartans commanding 30,000 free Greeks! The enemy outnumber us a paltry three to one, good odds for any Greek. This day we rescue a world from mysticism and tyranny and usher in a future brighter than anything we can imagine. Give thanks, men, to Leonidas and the brave 300! TO VICTORY!" -Dilios

"I see in your eyes the same fear that would take the heart of me. A day may come when the courage of men fails, when we forsake our friends and break all bonds of fellowship, but it is not this day. An hour of wolves and shattered shields, when the age of men comes crashing down! But it is not this day! This day we fight! By all that you hold dear on this good Earth, I bid you stand, Men of the West!" - Aragorn

"I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched C-beams glitter in the dark near the Tannhäuser Gate. All those moments will be lost in time, like tears in rain." - Roy Batty

"Troopers! I have just received new orders. Our superiors say the war is cancelled, and we can all go home. Bison is getting paid off for his crimes, and our friends will have died here... will have died for nothing. But... we can all go home. Meanwhile, ideas like peace, freedom and justice - they get packed up. But... we can all go home.

Well... I'm not going home. I'm gonna get on my boat, and I'm going up-river, and I'm going to kick that son-of-a-bitch Bison's ass so HARD... that the next Bison wanna-be is gonna feel it. Now who wants to go home... and who wants to go with ME!" - Colonel Guile

"Imagawa has 40,000 men marching toward this place? I don't believe that. He 'only' has 25,000 soldiers. Yes, that is still too many. So, Sado, you want me to surrender. What if we do surrender? Will you get content with losing your life that way? Or what if we hold on like Katsuie wants me to? What if we stay here in this castle, lock it up, and wait until the Imagawas lose appetite and stop the siege and go home? We will be able to prolong our lives for five or ten days, and what we cannot defend will still be undefendable. We are at the bottom of the pit, you know. And our fate is interesting. Of course the misery is too great, too. But this is how I see it: this is a chance in a lifetime. I can't afford to miss this. Do you really want to spend your entire lives praying for longevity? We were born in order to die! Whoever is with me, come to the battlefield tomorrow morning. Whoever is not, just stay wherever you are and watch me win it!"

 Flinty wrote:
Obligatory mention of Bill Pullman in Independence Day.

Not a movie, but its a great monologue - Stellan Skarsgard's Andor piece was excellent.