Calibre is an eBook organizer that puts your digital library in a single searchable, organized place. The program makes it easy to keep track of your collection, and if you do not own an eBook reader, its simple interface makes it a functional program for reading books on your laptop, netbook or desktop computer.

The beauty of Calibre is its simplicity. If you want to edit title or author information about a book, all you need to do is double-click the entry and start typing. Calibre will quickly make the changes to the eBook's metadata. You can also send your files from your computer to your eBook reader with the click of a button, and Calibre supports most eBook readers on the market. You can check out a full list of supported devices on the program's website.

If you're planning on moving a bunch of books from your computer to your eBook reader, Calibre is an essential tool for cleaning up file names before you start transferring. There are a few downsides, however. Calibre's RSS support doesn't work very well, so if that's a major feature for you, you're better off looking elsewhere. The program has a simple but unremarkable interface with a few unnecessary icons. Finally, its functionality overlaps with similar software from major eBook companies like Barnes & Noble and Amazon, so if you're already using one of these services, you might not need to switch over to this open source solution.

Nevertheless, Calibre works well and supports pretty much every eBook format imaginable. Because it's open source, it will likely receive a slew of updates in the future, and it displays books in a very simple and intuitive way. If you're a big eBook fan and you're looking for a way to organize your digital collection, this is a functional, feature-rich program.