For reference, my fandoms are mainly Buffy (not Angel, which I still haven't watched) and Sherlock Holmes (ACD original only, please). I can probably write something amusing enough for the Sayers Wimsey books, ST:ToS, and Babylon 5. Maybe Harry Potter, even.
(Man, these promises always scare me. The tag fic game scares me too, every time. Yet it prompted some of the best stuff I've written, so I'll take the risk!)