During the past few days, I've been experimenting with a number of different methods for reading e-books (Barnes&Noble desktop ereader, iBook on iPhone, Adobe Digital Editions desktop, Stanza for desktop and iPhone, both Windows and Mac). I have found the best e-book desktop reader solution, in my opinion, is EPUBReader.
EPUBReader is a Firefox add-on which lets you read e-books in the popular ePub format right in your browser. You don't need to install any additional software.
With EPUBReader installed, when you click on a link to an ePub file, the file is downloaded, processed, and displayed in a Firefox tab ready to read. Open and read previously downloaded ePub files using File-Open File… from the Firefox menu.
I have been testing the various readers with the CK12 Foundation's Geometry e-textbook. Click the thumbnail below to see an example of how well the special mathematical content is rendered by EPUBReader. I found this far superior to any of the other free e-book readers I tested.
A shortcoming of EPUBReader is the inability to annotate the e-text with highlighting and notes. You can add bookmarks, however.
EPUBReader is available in 23 different languages including English, French, German, Italian, Japanese, Portuguese, Russian, Chinese, and Spanish.
On a personal note, I no longer use Firefox as my browser of first choice. Unfortunately, I was not able to find a similar extension for either Safari or Chrome.
DISCLOSURE OF MATERIAL CONNECTION: http://cmp.ly/0