Some are the following characters are deceased, so they can't happen, but these are my favorites.
Jugo & Kimimaro (I love their bond to death. Honestly, I feel like it's canon. To me, it is anyways. Pisses me off that they didn't see or think about one another when Kimimaro was revived. I was hoping, somehow, Jugo would sense his cursemark or that Kimimaro would wonder about Jugo. Still, we have the anime, although I'm sure the won't give us proper filler of things that should've happened, in my opinion)
Neji & Tenten (Before you know...I still have hope. I love NejiTen! I just see Neji as her white knight from royality and Tenten is the kick ass middle class girl)
Suigetsu & Karin (I love them. Karin is more bitchy, but that's her deal. I hate when people compare Suika to NaruSaku. I see the similarites, but I like Suigetsu way way more than Naruto. Anyways, yeah, Suika rules!
Shikamaru & Temari (It all speaks for itself)
Kiba & Hinata are so cute and I understand they won't happen, and I'm completly okay with that since I don't hate NaruHina, and I'm okay with Kiba finding a new girl (Brand new, not a familar character)
Sai & Ino (Just very artistic. Sai and Ino just work. Sai is about emotion and sees nothing else, while Ino cared about looks for a while. They just fit)
Kakashi & Mei (Crack, but canon in my mind)