James Joyce's Ulysses: Critical Essays. That book has a different scholar focusing on each chapter of Ulysses, and a lot of times I find they go so deep they may lose some of the forest for the trees.
This is a great example of over-the-top analysis- the chart of where all the characters in Wandering Rocks are, and at what time. I'm not sure it really adds much to the understanding of the chapter, as the reader is not living the book in the same time as the characters, but I loved how they made such an effort to include the chart, even putting in special fold-out pages.
Later on, the chapter including the Citizen has a listing of all the references and what they "might" mean.
Charts! Graphs! Whatever it takes!