Books for Mac OS X (MIT License) is a useful little application for cataloguing, er, books. It has a very useful Quick fill button, which allows me to enter a book's title, and the program then fetches the book details from Amazon et. al. Besides a number of useful importers, Books can export my list of books into a folder, as PDF or tab-delimited data. According to its German Web site, the program is no longer being developed, but a message on the Books' site says it will be. I've used Books for some time, and I'd hate to see it go away.