Sometimes, if a game is cheesy enough, either your character, or the enemies will make snide taunts, action movie style. Alot of times, this can be funny.
I got FarCry the other day, and nearly laughed my ass off when the enemy yelled at me “I’ll shoot you in your FACE!”
I’m sure Duke Nukem 3D had some gut-busters, but it’s been so long since I’ve played that game. So what are your favorites?
Gorf was the original taunting game, wasn’t it?
In Heroes of Might & Magic III, the Devil and Archdevil units have a little built-in feature: when you move the targeting pointer over them while considering an attack, they go into a slight crouch and beckon with one finger as much as to say “C’mon! You wanna piece of me? C’mon!”. 
Duke Nukem 3d includes the line “I’ll rip off your head and shit down your neck!” What makes it doubly funny is that it wasn’t just an idle threat.
I remember Gorf!
There was also Bezerk. When you ran out of the room early, you’d get “Chicken! Fight Like a Robot!”
Wasn’t the Monkey Island series of games also about taunting?
Wizard of War. It had the early 80’s robot speech, monotone and without expression. The programmers had to approximate the phonetics to get the speech to sound right, so the opening taunt sounded like “Aaee am thee weezard of wor hahahahaha.”
The only other taunt I remember from that game was “Iff yoo hert maaee baybeez Aaeell rost yoo ahlive hahahahaha.”
Simply name your character “1980’s Action Hero”, and proceed using any 80’s action taunts that you wish.
“I’ll be back!”
“Yippie Ki Yay, Motherfuckers!”
Also, talk about doing some “Van Damage” a lot. That should annoy your enemies and amuse your teamates. Especially if you’re really good. 
Insult sword-fights!
“You fight like a dairy farmer!”
How appropriate. You fight like a cow.
I: You make me want to puke.
A: Looking at you makes me think someone already has.
Monkey Island rocks.
Interesting historical note: the original Monkey Island swordfight insults were written by Orson Scott Card.
I: I got this scar on my face during a mighty struggle!
A: I hope now you’ve learned to stop picking your nose.
“All your base are belong to us”
Sorry, it had to be said.
IIRC, Sega’s Space Fury had a vector-graphic one-eyed alien that taunted you between rounds. I seem to recall that the first one was “Ah, a creature for my amusement. Prepare for battle!”
In Rockstar’s Manhunt, you sneak around a lot in the shadows and the Cerberus unit say ‘Only a pedo(phile) would hide like this’
And the cops say something like ‘You should see the last hobo CCPD had to bring in’ and ‘Here, boy. Want some pills?’
"We have a visitor. Stay a while. Stay FOREVER!!!"
…a cookie to whoever names the game!
Impossible Mission, of course, from the good old days…
Many years ago, I was playing The 7th Guest late at night. I plugged in headphones so my parents wouldn’t hear me at the computer (wishful thinking, as will be evident…). I was exploring the cellars, accessible through the pantry, before I knew that a map of the cellars was available on a rug in an upstairs bedroom.
I turned a corner, ended up in a dead-end, and Stauf’s creepy voice boomed out, “Feeling … lonely?”
I jumped and shrieked. My parents awoke. That was the end of my gaming for a few days. 
:: …hands Ino a cookie. ::
Twenty-five years later, my stock line after an early victory in networked Starcraft is “You were an… adequate… opponent.”
[/dork]
“I never asked your sister out!”
and, from the same game,
“I told myself; Mario! Take it easy!”
Vice city, of course. Love tose guys.
And from the mouth of a startled, soon-to-be-very-dead bad guy who spots the Punisher emerging from the shadows in the recent (and very good) Punisher game:
“Shit on a Shingle!”