Staffan said:
Yes. Full-blown speeches have a tendency to go something like this..."
Maybe it's just my players then, hehe. We tend to have combat-light, RP-heavy games. The players in my game will also give speeches from time to time, or other neutral or good NPCs. If we're talking stricktly pre-written speeches, it's not something that happens often, perhaps once every eight games or so. But I find it handy to write the speech (sometimes borrowing lines here and there from literature), even if I don't use it, it gets me into the mindset of that particular NPC. It allows me to better understand the NPC, think through their exact motiviations, passions, etc and see how it all affects the game and the RP. The best one I did recently was before a massive battle... I even timed it to the music I had playing in the background while DMing (Journey to the Line by Hans Zimmer from the movie The Thin Red Line, speech began at min 2:07).
End of Brigadier Lord Tellinius' speech to the Ironstone Regiment:
"Warriors of Damara,
You have long seen what tyrants can bring to the world.
You have seen what injustice they spread,
And you have seen their evil in your own homeland.
My homeland.
We fight this day so that others would not anguish as you have.
Battles against the forces of darkness have been lost and won before,
But never without hope!
For we were always there, always in reserve.
Who are they who would take the suffering of others?
Who are they that would right the wrongs before us?
Who are they with the courage to do all this?
We are the last of heroes,
We are valor!
By the god’s will, I pray,
I wish not one man more than those that stand with me this day!
So, hold fast to the ground you defend,
And let the enemy tremble as we take his!"
That might be a nice line in a not-so-serious game - provided the player screw up. 
