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.
Animation Age Ghetto: The movie looks like an Animesque kids' cartoon; and the story can be mistaken for a standard fantasy story about quests and magic and unicorns. In truth, it's nothing of the sort. The book has won many awards and is considered by fans and other authors to be one of the best works of fantasy ever written and the film is a beautifully animated note Through a conjunction of Rankin/Bass and animators who would later to become part of Studio Ghibli faithful adaptation of the story.
Awesome Music: The movie has a soundtrack that is way too awesome than a movie about unicorns has any right to be.
Big Lipped Alligator Moment: The bit with the tree falling in love with Schmendrick is a peculiar bit of broad comedy plopped down in the middle of a wistful and melancholy work. It's handled much more subtly in the book. However, it fits right in with the Central Theme of the book, as the tree croons, "There is no immortality but a tree's love." Sound familiar?
Cult Classic: One of the most beautiful and deep forgotten gems of animation.
Ear Worm: Quite a few of the songs, annoyingly so.
Genius Bonus: Molly's initial reaction to seeing the Unicorn is sad enough in its own right - but when you understand the mythology behind unicorns (namely that they're the embodiment of Nature Adores a Virgin), her line of "Where were you when I was new?" takes on a whole new level.
One-Scene Wonder: Numerous characters/voice actors quickly come and go, but Rene Auberjonois stands out as The Skull.
Painful Rhyme: "When the first breath of winter through the flowers is icing / And you look to the north, and a pale moon is rising"
Viewer Gender Confusion: Celaeno is constantly referred to as a female throughout, and has the breasts to prove it, but when "she" is talking to the unicorn telepathically ("Set me free...we are sisters, you and I..."), the voice is clearly male.
Tough Act to Follow: In a 1978 preface, Peter S. Beagle remarked that The Last Unicorn would "haunt the rest of (his) career," and that he grew "increasingly shy of talking about (it)." In this case, it seems that it wasn't the writing that Beagle grew tired of—it was the book. At San Diego Comic Con 2006, his remarks on Unicorn indicated he's not tired of the book so much as writing it was in some ways extremely difficult and painful... in contrast with other stories, which seemed to flow from him freely. He stated he had to fight to get the story written. Not something he enjoys thinking about.