Among the moments from Die Hard that always make me laugh are, 

Supervisor: Attention, whoever you are. This channel is reserved for emergency calls only... 
John McClane: No f*cking sh*t, lady! Do I sound like I'm ordering a pizza? 

Hans Gruber: "Now I have a machine gun. Ho ho ho." 

and my favourite of all,

Sergeant Al Powell: In fact, I think he's a cop. Maybe not LAPD, but he's definitely a badge. 
Dwayne T. Robinson: How do you know that? 
Sergeant Al Powell: A hunch, things he said. Like being able to spot a phony ID. 
Dwayne T. Robinson: Jesus Christ, Powell, he could be a f*cking bartender for all we know! 
