X-Men
I love the X-Men. My favorite cartoon series is X-Men Evolution and I ship Toad/Nightcrawler intensely. There are other ships, but none that I'm just as passionate about. That said, you'll probably find a little bit of everything here.
I'm also a great fan of the movie-verse and my favorite ship there is Pyro/Iceman. Especially because in the overall history of X-Men, Rogue/Gambit is my top ship of all time. (I know! Het!!)
So far I've written these pairings in various X-Men series:
Toad/Nightcrawler
Avalanche/Quicksilver
Pyro/Iceman
Shadowcat/Colossus
Probably more to come.