AP vs Chicago isn't some March Madness event you haven't heard of. It's a lively website that provides a detailed comparison of "house style" for the Chicago University Press and the Associated Press (AP). Written by Karen Yin who states she has more than 20 years of experience as a copyeditor, it is packed with detailed comments on the finer points (and periods, and question marks) of self-expression that may seem trivial--until suddenly you need to know the answer. Although it focuses on the AP and Chicago style guides, the site includes forays (not, of course, Faurés) into the MLA and New York Times style guides.
If you woud rather read about serial commas than serial murderers or you just can't tell an ellipsis from your elbow, this is the site for you.