First thing that comes to mind

[Marter]

In real life: "Run!"
On the screen: "Someone's going to die" or "Get off my lawn"

 

[Mr.Squishy]

Empty halls with a lone gunman walking around, reloading, possibly bodies limp on the floor or propped against the wall. I have no idea why, it's just what first came to my mind.

 

[bam13302]

http://www.explosm.net/comics/966/
*chung chung* whose got front seat now b****!

 

[Darth Caelum]

You may be right, but i have a shotgun.
Me + Shotgun= You DEAD.

 

[socialmenace42]

If i heard it? I'd get kinda paranoid about zombies VERY quickly...

If I then also heard a chainsaw I'd start running

 

[Segadroid]

"Ooooooooh shit..."

 

[child of lileth]

Right this second, the original Quake. I don't know why though.

 

[TriggerHappyAngel]

I call Shotgun!
*Chung Chung*
I mean USE Shotgun!
*BANG!*
>

 

[Silent Eagle]

Explosion. The effect that said shotgun will have on my xbox 360 if i cant get it fixed. Which i kinda look forward to.

 

[Serioli]

Francis from L4D

'Merry Christmas'

 

[Mr. Self Destruct]

http://www.youtube.com/watch?v=Wp_K8prLfso

i can embed pictures, just not videos D:, anybody care to lend a hand or ten?

 

[Me55enger]

"it seems that last time we met, Punk, I had fired six shots. That was your lucky day..."

*shifts cigar to other side of mouth*

"so tell me Punk" *Chung Chung* "do you feel lucky now?"

If Clint Eastwood did revenge...

 

[Wardnath]

Someone mentioning WoW on the OT (WoW off-topic).

Edit: Like this.

 

[MASTACHIEFPWN]

Oh please, try to hold that piece of crap up against my Pancor Jackhammer!

 

[Nikajo]

Doom probably. Used to play that a lot when I was younger

 

[kebab4you]

"Taaank!"

 

[CoverYourHead]

"So it's going be one of those days, 'eh? Alright..." *straightens hat* "Lets do this."

 

[tehweave]

I'm here to kick ass and chew bubblegum. And I'm all out of bubblegum.

Either that or...

Saddle up... Lock and load. (points for whoever knows where that comes from... it's more modern than you think)