These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Crowning Moment of Awesome: Ranma calling out (and subsequently trashing) Kuno for not defending Akane's honor after Kodachi called her several very offensive names despite his supposed love for her.
Akane gets one when she beats Kodachi... with a ZA WARUDO impression. OUCH.
Genma has one by convincing Akane to train in the Umisenken
Kasumi whupping Shampoo's ass in Chapter 16. This is even more awesome by the fact that in the previous chapter, Akane, Ryoga, Kodachi, Mousse, and Kuno teamed up had tried and failed to best Shampoo.
Crowning Moment of Funny: Several, but the first would probably be the unveiling of Akane's inner Star Wars geek when Ranma beats up the Martial Arts Sci-Fi club for her and she pockets one of their toy lightsabers.
Ranma and Akane learning that Tatewaki and Kodachi are brother and sister.
Chapter 14 Training Montage with Donny Osmond, complete with musical numbers, PLURAL. And one of them is the famous montage song from South Park!
The final battle for Ranma plays out as an epic knockdown, drag-out fight where the previously implacable Shampoo is brought low, her guns destroyed, armor smashed and she's bleeding profusely. And as it moves to the epic crescendo of what should be the moment of triumph, Shampoo turns the tables on Akane with the Hiryu Shoten Ha. After all that, the training, the montage and everything, Akane loses. It just... goddamnit all.
Kasumi's flashbacks throughout the Sino-Japanese War Story Arc.
Akane's talk with Kasumi after she lost is one big moment where you'll keep finding something in your eye as she breaks down exactly what she has lost by losing to Shampoo.
Troll Fic: The entire point of the story for some people. On how many levels (if any at all) depends on how highly you think of the author, but various options are listed in the talk page.