I'm gonna make make make you work

Folks are doing the request-a-drabble thing, and I'd like to hop on the bandwagon, but it ain't going to be free! I have a fic-related trivia question - first five people to answer it correctly can request a drabble. Give me a fandom and a prompt; it'll be gen unless otherwise requested (partly owing to this discussion of awesome over on tinman_meta). Fandoms I'll happily write in: pretty much anything I have an icon of. (Ask if you're not sure.)

I wrote a story a while back called The Key in response to a marvelous prompt from kseda, which was ostensibly a Tin Man/Return to Oz crossover. However, it also contained a further hidden crossover. I didn't say anything because I thought *someone* would pick up on it, but so far no one has mentioned it. It's a "concept crossover" - there are no actual characters from the other fannish universe present in the story. Answers are screened.

HINT (select the next paragraph with your mouse to see it): Remember the curse that was placed on Cain and Glitch. One of them was always an animal when the other one was human; they would switch periodically. To break the curse, they had to perform a specific action dictated by the person who put the curse on them.