Forgot to mention: Yuletide signups are now open. If you’re not sure what I’m talking about, there’s a FAQ here that explains a lot. (And also this, but it’s kind of more “entertainingly helpy” than “actually helpful.”)
Signups will be open until the 28th. Further updates will be posted on (official) and (community); also, this post is worth keeping an eye on.
Yuletide is a lot of fun, and includes many things you might not class as “fanfic” in the normal way of things. I encourage people to check it out!