Star Trek IV: The Voyage Home/YMMV

"Sulu: I love this town!"
 * Anvilicious about its Green Aesop.
 * This isn't even a case of YMMV, the movie really wants you to know how ENDANGERED whales are ALL OF THE TIME!
 * The peak of this is probably the tour at the Cetacean Institute, which is only kept from being a literal lecture to the audience in that the doctor doesn't turn directly towards the camera while she speaks.
 * Base Breaker: While it's one of the more popular installments, there are fans who see it as a glorified version of Tarzan's New York Adventure.
 * Big Lipped Alligator Moment: The bizarre dream sequence that occurs during the first time-jump.
 * That sequence was largely filmed with primitive CGI. Since this was The Eighties, the technology couldn't be used to render anything remotely realistic, so they simply nixed the realism part in order to pioneer a new filming technique.
 * Fanon: It's suggested by official sources, though not confirmed, that the Enterprise-A was not a brand new ship but was the ship Yorktown (mentioned early in the film as suffering from the probe's effects) and was rechristened to be the Enterprise. In any case it is question of how quickly they were able to make a new USS Enterprise when the first was destroyed only about 3 months prior in story.
 * Hilarious in Hindsight:
 * Sulu's line "San Francisco, I was born there..." has gotten more hilarious since George Takei came out of the closet. Originally it was funny just because of the fact Takei was born in San Francisco, but the revelation adds even more humor to:


 * Catherine Hicks, who plays Dr. Gillian Taylor, went on to play Mrs. Camden on the TV series 7th Heaven. Her on screen husband, Stephen Collins, played Commander Willard Decker in Star Trek the Motion Picture.
 * Alternatively, Kirk really is from outer space.
 * Mary Sue: Not any of the characters, necessarily, but this movie portrays Federation medicine as ridiculously more powerful and advanced than it is in any other iteration. Even The Next Generation, set quite some time later, would not have had someone able to take a pill and grow an entirely new functional organ (else Picard wouldn't need his artificial heart), and Chekhov's injury probably would have required actual surgery. The omnipotence of future-medicine seems to exist mostly to facilitate Bones' griping about the (relatively) primitive state of medicine in 20th century.
 * Memetic Mutation: "Nuclear Wessels"
 * "Admiral! There be whales here!"
 * Straw Man Has a Point: The pompous Klingon ambassador demands justice in response to Kirk killing Kurge's crew in the last movie, which cues Sarek to explain just how villainous they really were. The Federation president assures everyone present that Kirk will face Federation justice, which the Klingon ambassador scoffs at. Out of all the things the crew did in the last movie, no one is going to bat an eye over what happened to Kurge's crew. However, the Klingon ambassador nonetheless winds up being right to scoff at "Federation justice." All charges of theft and sabotage of Starfleet property are dropped, and Kirk's violating the chain of command is "punished" by a demotion to Captain and the command of his own ship - the two things he wanted anyway.
 * Considering that aside from killing Kruge and his crew of terrorists, all of Kirk's crimes were against the Federation and thus the Federation can decide on whatever punishment they like for it, the ambassador doesn't exactly have a pot to piss in there.
 * In fact, under international law the only way the Klingon Empire can demand justice for the killing of Kruge -- that is, to claim that Kruge's death was murder under the law rather than legitimate self-defense vs. a terrorist -- is to claim that Kruge was not a terrorist, but instead a loyal member of the Klingon Empire engaged in activities both perfectly lawful under Klingon law and sponsored officially by the Klingon government. Which means that the ambassador is basically taking the legal position that the Klingon Empire just committed an act of war vs. the Federation over Genesis. It's no wonder the Federation is politely ignoring him -- the ambassador's legal position is not only incoherent nonsense, but officially acknowledging it lands the Federation in a war they don't want.
 * Alternately the ambassador could be claiming that Kruge was an entirely innocent Klingon who just happened to be sailing through the area conducting a peaceful survey of local asteroids when the Federation proceeded to blow him up for no reason, and that all claims of 'terrorism' are just to cover up the Federation's habit of murdering random Klingons in drive-by photon torpedoings, but that would fall into a diplomatic category known as "obvious bullshit is obvious", the established practice for which is to politely listen to the ambassador rant and rave and then forget everything he said three seconds later and go take an early lunch.