Nisemonogatari, the sequel to Bakemonogatari, has several interesting characters with very witty fast cut dialogue, amazing visuals and Akiyuki Shinbo's unique directing style, not to mention the subtext of the meaning of original and imitation regarding everyday life. But you will all fondly recall the moment where you nearly died of laughter or shame when Koyomi brushed his sister Karen's teeth and it was supposed to remind you of something.
If someone knows anything about Brain Powerd, it's most likely to be the opening, which mainly consists of nude shots of the female characters.
Cannon God Exaxxion is a near-Eva-level deconstruction of Super Robot stories, particularly of the "aliens invade, teenager's Mad Scientist grandfather gives him a Humongous Mecha to fight them with" variety and has a lot to say about the nature of heroism and the truth. Ask people about it on the Internet, though, and all you'll hear is talk, often derisive, about certain scenes with Lolicon undertones (and, uh, one with possible overtones, but still).
The anime of Charger Girl is best known for the scenes where Plug wets herself.
Cross Ange is more well known for the very attractive females wearing Stripperiffic pilot suits, having a lot of softcore Yuri scenes and the controversial prison rape scenes in the first two episodes than the actual main story of the show.
There's a scene in Darker Than Black where November 11 lounges around Amber's headquarters buck-naked. Naturally, fan tributes kind of fixate on it.
Divergence Eve has a very serious and complex sci-fi plot, but that doesn't get talked about much. Instead, most people focus on the fact that almost every female character (not an exaggeration) has breasts the size of their heads and wears extremely tight-fitted clothing. It's almost impossible not to talk about the fanservice because of how omnipresent and out of place it is with the seriousness of the plot.
Eden of the East is an Ontological Mystery story that revolves around a man who wakes up with eight billion yen and no memory as he seeks to find out who he is, why he erased his own memory, and just what the secret organization that gave him all that money expects him to do with it. You would probably not know this from talking to its fans, however, because they're all too busy giggling over this.◊ And once they get over that, they must contend with the vast horde of naked dudes that shows up later in the series.
Elfen Lied is probably best known as that manga (or anime) with huge amounts of nudity and gore. Most of the nudity is in the context of Mind Rape or psychological abuse, but that small detail easily falls to the side.
Fairy Tail has lots of well endowed female characters who wear skimpy clothes and have several scenes where they are naked. The male characters also get some of this. Hiro Mashima's previous series Rave Master was also like this but mostly in the second half.
Food Wars! features cooking treated as super Serious Business and the resulting Food Porn, with scenes that may make the viewer wonder "am I watching a cooking competition or a duel that decides the fate of the world?" However, it is also well-known for the many...vivid reactions of often-female characters eating these delicious dishes, making the viewer wonder "did the cook put aphrodisiacs in the food?"
If you know just one thing about Free! it's probably that a bunch of hot muscular swimmer guys get half-naked a lot. As the anime seems to have been deliberately intended as a female-directed equivalent to the all-prevalent moe fanservice anime, this was probably expected, and the producers and advertisers have certainly made the most of it.
The only things most people seem to remember about Gargantia on the Verdurous Planet are the scene where Amy dances for Ledo in a skimpy outfit and the Beach Episode, despite the fact that the rest of the series has about as much fanservice as a Disney movie.
Gantz is about a group of people about to die that are cloned by a spherical machine and forced to hunt aliens whom live secretely on earth in return for their "new lives", being full of moments of thriller and drama because of that. However, most people likely know it for two reasons: first, the extreme violence and gore; second and last, the large amounts of nudity and sex. The fact that the manga also features random and almost naked women in its chapters covers doesn't help.
Highschool of the Dead is about a group of teenagers trying to find their missing families amidst an unexplained zombie outbreak, having to fight their way through hordes of zombies and surviving the outbreak. But with all the panty shots,cleavage,gainaxing, innuendo, and sex-related humor, it becomes easy to forget about the plot-related aspects.
Japan Animator Expo is a series of shorts organized by Hayao Miyazaki (the brains behind Studio Ghibli) and Hideaki Anno (creator of Neon Genesis Evangelion). They're a means for names in the anime business to create things without interference from production committees or studio censors, and what gets produced are hugely varied in themes but always visually amazing, whether it's sweet, action-packed, breathtaking, humorous, profound, depressing, or anything else. However, the only short that gets a lot of talk, besides the Evangelion ones, is "Me! Me! Me!" a music video about an otaku's fever dream that consists largely of identical crowds of the same woman gyrating half-naked or fully naked eager to jump (and eat) his bones, set to pulse-pounding techno/rap.
Keijo!!!!!!!! takes this trope and runs with it. This manga is about a World of Buxom where pretty girls in swimsuits fight each other in pools and the only legal weapons are their breasts and butts to smack the opponent with, as well as some special moves they may have involving either. Which is exactly why people read it. If readers stick around, they'll find that Keijo is an over-the-top fighting anime that treats itself completely seriously, while managing to not just be mindless fanservice fodder.
Killing Bites's finale had a scene where the muscular, shirtless Leo pins Yuuko to a wall and tells her she's his slave now. It lasted about two minutes and both the characters involved were minor... but to this day, every thread discussing the show inevitably includes a screenshot of that scene.
The Stripperiffic heroine of Kill la Kill makes the series a Guilty Pleasure by design for many viewers. However, those who endure often come to appreciate the series' other strong points, such as humor, intense fights and its larger-than-life characters.
Later seasons proudly fly the fanservice banner, making Nanoha known pretty much as a Girls' Love series with magical girls in it. It's one of the few to have adult females in an (ambiguous) relationship and even rarer in that they adopt a daughter.
The best known of the Naruto fillers is the pre-timeskip arc where Naruto and Team 8 travel together. The most remembered scene in that arc is without a doubt the waterfall scene. Naruto spots a naked girl dancing in a waterfall. Unknown to him, it was Hinata practicing a new jutsu.
Mention Negima! Magister Negi Magi and most people will inevitably think of Fanservice or Clothing Damage. Yes, the manga has a lot of fanservice, but it also has a ton of Character Development, an epic plot, and a ton of awesome fights. Still doesn't keep the fanservice from overshadowing just about everything else in the popular perception of the series. It doesn't help that the early volumes were more fanservice-heavy than later ones. To make matters worse, a lot of people's only exposure is the first anime, which is severely lacking in a lot of the more combat oriented storylines. Ironically, the second anime lacks any fanservice what-so-ever.
In-universe, Takane D. Goodman is remembered by others for getting naked a lot (although never by her own choice) and little else, except for her co-workers, who try to console her about that.
In fact, Takane is so used to it that, when she challenges Negi (and loses) in chapter 345, when she ISN'T stripped of her clothes (which is how Negi usually and accidentally wins against her a lot), she's insulted, and DEMANDS that he undress her.
Occultic;Nine is a paranormal mystery series where one of the characters is a huge-breasted genki girl. Lovers and haters of the series focus on her breasts and ignore everything else about the show.
The seventh One Piece movie The Giant Mechanical Soldier of Karakuri Castle is an adventure involving a golden crown, giant robots, a giant turtle, and a (non-canon) explanation for how Luffy got the name for his Gear power-ups. All of that is brushed aside for Nami and Robin's breast enhancements, constant bouncing, and fetishistic outfits.
While the anime adaptation of Queen's Blade has a fairly dense story it's still part of franchise that won over tons of fans with attractive character designs and sexual content. As a result a lot of the anime's viewers didn't care and ignored the plot of the anime in favor of sexy scenes of their favorite characters.
The anime adaptation of Rosario + Vampire contains much more fanservice than the manga, with breast and panty shots galore, which has caused some backlash from certain parts of the fandom, but usually not to the point that it ruins the series for them. At least not until the 2nd season, which largely discards the plot in favor of even more fanservice to the point that most Establishing Shots include someone's panties.
Parodied in Sayonara, Zetsubou-Sensei in an episode about how people will easily get distracted by something and completely ignore the more important issue. A straight example is when Chiri battled aliens but nobody remembers her deed as the sole witness was completely fixated on her bizarre underwear. Another straight example that lampshades the entire episode was when Nozomu was lamenting over how the viewer survey answered that they were more interested in the fanservice segment where Komori was flirting with Majiru over the alien invasion plot. Even the aliens were more interested in that segment than the invasion itself, which is why they were so easy to defeat.
Seikon No Qwaser has a number of cool elements, such as memorable characters, literal Elemental Powers, Character Development and kickass battles. Sadly, all of that tends to be overshadowed by the rampant breast feeding (since those elemental powers do run on breast milk) and bondage.
Sekirei has a strong, character-driven plot and excellent fight scenes. But what most people know about it is the World of Buxom and fanservice bordering on softcore at times. Many are surprised to learn the author is a woman.
With Simoun, everyone remembers the underaged lesbian powered airplanes.
Sky Girls, the spiritual predecessor to Strike Witches and Vividred Operation was about somewhat cute girls in suggestive skin tight suits piloting flying Mini-Mecha and battling aliens aiming to destroy humanity. It had decent characters and an engaging plot with many twists, but... well, just look at the trope name again.
Strike Witches is ostensibly about an elite flying unit battling an alien invasion with magic, but apparently the only people possessing the right kind of magical powers are pre-teen and teenage girls willing to fight aerial battles in their underwear. Countless panty shots ensue. In fact, it's easier to count the scenes without panty shots.
Vividred Operation, by the same director, is a pseudo-Magical Girl series about cybernetically enhanced girls fighting giant evil robots. But more importantly: they don't wear pants (and when they do, they're very short ones), and there are lots of ass-shots.
So, I Can't Play H! has a fairly intricate plot concerning the balance between the human world and Grimwald. It also features gorgeous art and character designs by Kanai Yuuko, with animation by Studio Feel. Yet, if you go by most forum discussion, you'd swear the series was nothing but boobs and Lisara being stripped semi-nude in all of her fight scenes.
To Love-Ru does have a rather diverse cast and interesting universe, as well as a number of serious emotional scenes. If you talk about TLR to anyone though, that probably won't be the first thing that comes to their mind. Not that you can blame them. Try looking for even one manga chapter without gratuitous nudity and/or underwear shots. And the sequel series Darkness is even worsein this regard.
Witchblade is the story of a woman trying to make a life for herself and her 6 year-old daughter after a massive disaster takes away everything from her, including her memories; all while dodging Child Protective Services and getting caught up in a corporate power struggle. It's also the story of said woman turning into a superpowered warrior with a ridiculously Stripperiffic outfit and getting into fights that are the very definition of Orgasmic Combat. Guess which part people remember more (hell, guess which part is used to market the show?)