The salt shaker full of cocaine is opened when they're bombing down the freeway in a convertible...predictably, the cocaine catches the wind and flies all over.
Dr. Gonzo: Jesus! Did you see what Goddddddd just did to us, man? Duke: God didn't do that, you did it! You're a fuckin' narcotics agent! I knew it!
The scene with the hitchhiker.
Hitchhiker: I've never ridden in a convertible before! Duke: Is that right?
The bar scene in the first hotel. Duke is still feeling the acid and sees the floor as flooding with blood: "We'll need a pair of golf shoes. No other way to walk in this muck." He then starts seeing the crowd around him as walking lizards. This is all nightmare fuel, even when a hallucination of Dr. Gonzo is speaking gibberish. Then, Duke spouts this line: "PLEASE!!! TELL ME YOU GOT THE FUCKING GOLF SHOES!"
Though Duke and Dr. Gonzo are taking plenty of drugs while driving, it's imperative that they be sober while they check into the hotel. Dr. Gonzo offers the aforementioned acid to Duke.
Duke:(gulps down the acid) How long have I got? Dr. Gonzo: As your attorney, I advise you to drive at top speed, and it'll be a damn miracle if we get there before you turn into a wild animal. Duke:(begins whacking away at Dr. Gonzo with a fly swatter, and missing. Under his breath:)pigfucker pigfucker pigfucker!!(Gonzo notices nothing, Duke irritatedly speeds up)
While Duke and Dr. Gonzo are in their hotel room, Duke, who is still high as a kite, continues hallucinating while staring out the window at the nearest neon sign. The sober Dr. Gonzo's reaction is priceless.
Duke: There's this great big machine in the sky — kind of an electric snake — it's coming right at us. Dr. Gonzo:(completely deadpan) Shoot it. Duke: Not yet. I want to study its habits.
Duke is watching a highly inaccurate educational film about drugs stating the average "dope fiend" can be identified by how "his pants will be crusted with semen from constantly jacking off when he can't find a rape victim", then Duke reflexively takes a look at his own pants. Which are, in fact, crusted with something.
Duke: With a bit of luck, his life was ruined forever — always thinking that just behind some narrow door in all of his favorite bars, men in red woolen shirts are getting incredible kicks from things he’ll never know.
"You people voted for Hubert Humphrey, and you killed Jesus!"
Gonzo and Duke encountering Christina Ricci's Lucy slowly trudging across the road... "Oh shi..."
The scene where Duke first meets Lucy is funny and so unexpected. Dr. Gonzo tells him where his reserved room is. However rather get the rest and relaxation before their latest scheme he is promptly attacked by Lucy who proceeds to bite his leg. It makes it more, funny that Dr. Gonzo takes his time and even laughs at Raoul before fending her off and explaining who he is.