eCub is a free and simple .epub-converter and cross-platform tool to create EPUB compatible iBooks and to convert existing text- or xhtml-files into the ePub-Standard. EPUB files are generally compatible to the MobiPocket format, Adobe Digital Editions, FBReader, Stanza and many other readers and applications. The eCub-application offers fundamental tools to import text and XHTML files and create all the necessary components of an EPUB file-archive. It makes it easy to view and edit existing files, and check the generated EPUB, using external tools. On the developers Web Page, JulianSmart.com you can download a free Mac OS X version of eCub for personal use, which will run on Intel Macs and also on older PPC Macs with OS X 10.3.9 or later.
Jutoh is an another ePub-Software from the same developer Julian Smart, which is until now in development but yet available as demo-download. The Jutoh-Software promises easier WYSIWIG content-editing from the scratch with the possibility to generate ePub, MobiPocket or ODT-files. It is also not necessary to have knowledge of xhtml when formatting the iBook content.