Gorey Spoilery Alphabetic Guide to Harry Potter and the Half-Blood Prince (A-F so far) by naadi.
The art is so Gorey-perfect, and the text is so dark and amusing! I love things that can keep me snickering.
I think A might be my favorite one as a whole, but I loved the art for C best (Gah, Draco! I've never, ever felt sorry for him before!). F made me snicker the most. Heeheehee.
Just a reminder, in case the text in the link isn't enough: It does contain strong spoilers for HBP.
More Letters Needed NOW, please!