Dear Yuletide Author! (2013)

First: please enjoy yourself! The best fictions seem to be those that the author enjoyed writing. I'm going to give a number of possible prompts, and I'm hoping you'll find something that lets you take off. If not ... well, you can look at some of my bookmarks on AO3, and see whether those inspires any other ideas.

( Cut for lots of optional details that are still, you know, optiona; )