Willow Rosenberg and Tara McClay: Because they were just right. And I could believe that they were really in love, and hadn't just been thrown together for the sake of having a lesbian character on the show. And the way it ended broke my heart.
Willow Rosenberg and Daniel Osborne: Yeah, yeah, it contradicts what I just said above. But I liked Oz, dammit! And I'll always love the scene where she's practically offering herself to him, and he refuses to sleep with her because it isn't right yet.
Wesley Wyndham-Price and Lilah Morgan: Because they should never have been together, but they were, and in some strange and twisted way, it was true love.
Buffy and Spike: Because love redeems.
The two kids from My Girl, whose names I can't remember: Because the boy's funeral was the first scene in a film I can ever remember making me cry.
Laura and Shadow Moon, from American Gods: Because whether he knew consciously what he was doing or not, he loved her enough to bring her back. And all she did after that was protect him.
Sam and Joon, from "Benny and Joon": Because it's Johnny Depp. Because the character is incredibly sweet. And because the message of the movie is "love conquers all".
Joey and Rachel in Friends: Because the final episode of Season 9 made me squee like never before - odd, considering I always used to be a committed Ross/Rachel shipper.
Aragorn and Arwen, book version: Because it has all the things a love story needs to be great for me: passion, and true love, and a certain element of tragedy.
Han Solo and Leia Organa: Because I grew up on Star Wars, and they were the first proper couple I was really aware of. And just because. :)