FanChats💬submit your prompts!It's trope discussion Monday! What do you think about Crack Ships/Rarepairs? What makes them work for you? Can you recommend a fic that makes an unexpected pairing work well? 
Griselda Gimpel@FandomChats I'd definitely distinguish between the two, as a lover of both. There are some perfectly plausible - and in some cases out and out canon - rarepairs.
Anyway, I'm the self-appointed president of the Rarepairs Association, and I love writing them. Sometimes I'll get into writing a popular ship, but if a bunch of people have already written for the ship, there's a good chance that the fic I want already exists.
But with rarepairs, I'm creating what I want to see in the world. It doesn't exist. Ergo, I must make it myself.
For crack ships, it's about answering the question, "What would make this ship work?"
And now for some shameless self-promotion.
For rarepairs, I did an animatic for the John Gaius/Admiral Sarpedon (canon!) ship from The Locked Tomb.
https://archiveofourown.org/collections/TLT_Vids/works/51816238
For crack ships, I wrote a Greed/Jaeha crossover between Fullmetal Alchemist and Yona of the Dawn.