Significant NPCs should be granted memorable last words before they eventually expire at the hands of the heroes.
Except when it would be cooler for them not to.
Jabba: Ah! Strangulation! I'll take it on the chin. Not that I have a chin.
Leia: Shut up, you piece of worm-ridden filth!
Jabba: "Ridden?" It's a symbiont circle, my dear.
Leia: You're going to die. I'm going to kill you.
Jabba: Everybody dies! But not everybody lives as I live this moment!
Leia: Good last words.
Jabba: But I have so much more to say.
Jabba: Muse, attend me! Inspire me! An aphorism for the Ages!
Jabba: It's on the tip <choke>... of my tongue...
Jabba: Not that I... <hack>...
Jabba: Oh wait... <gasp>...