Titles in the Project Gutenberg catalog are already available as EPUB, but the quality of the formatting is not always the best, this is in part the fault of the original plain txt formatting of all PG titles but also the automated processing they employ.
What epubBooks does is take those plain-jane text files and convert them to a XML format using specially developed software, this allows them to be formatted in a very structured and precise way. These are then sent through more custom conversion tools which then turn them into high quality EPUB ebooks that not only look great but work perfectly on any current EPUB eReader, this includes the Apple iPad and iPhone, Android eReader apps such as Bluefire, Kobo Reader, Sony Reader, B&N Nook and BeBook.
When images are available for a particular PG eText, these are included in the EPUB making any Classic even more enjoyable…and way better than those horrible plain vanilla .TXT files!
Give it at try, head over to epubBooks.com, and start reading great, high quality free ebooks now!
UPDATE: epubBooks is currently working on a brand new tool that will convert the Project Gutengerg eText to the newest EPUB3 ebooks.
UPDATE 2014-09-04: A quick note to let you know that all ebooks are now available as EPUB3 and along with this, I now release every book in Kindle MOBI format too!