I'm pretty proud of this, So I think I'll take some time to show off.
I know there are a million sites for keeping track of books you want to read, but I wanted my own. As it is my own, most of the functionality will be disabled for you nonlogged in users - so you'll have to take my word for it.
-Draggable/Rearrangeable: Using custom fields, I mark new posts as defaulted to "want to read" (wtr) and they are placed in a custom db table that also keeps track of their sort order. When logged in, I can drag books around and it will ajax that book's new position in the list to the custom db table. When a book is dragged from the wtr list to the "currently reading" list, ajax changes the value of the custom field so that the book is saved as being read. When a book is dragged from the "currently reading" list, a new list appears for finished books. This again changes the custom field's status and the book is filed away and a second custom repeater field is populated with the year i read this book.
-Action Links: Each book has several action links at the top (more if I'm logged in), that allow me to search amazon or wikipedia for information about this book. When logged in, I have an option to download an ebook file for that book or edit the post.
-Responsive design: If I'm in a book store and want to quickly see what books I should be looking for, this site looks great on my mobile devices so that I can quickly see what books are next in my queue.
-Custom taxonomies: I use custom taxonomies to keep track of authors, and series information. In the future I will use that data to be able to pull up lists of all the books in a series.
github repo link in the footer for anyone interested in playing around with it.