I like plain text, because it is the rock solid bottom on which we can safely stand, whichever device, software or OS we use or will use in the future. And with fiction, not much more than plain text is usually
really needed. Not
much more... There already exist a number of tagged text formats, but for the use on my website I've come up with my own, with the intention of keeping it as basic and simple as possible both for the reader and the writer/editor. I have also written a tool that converts this format to HTML, from where it can be easily further converted to ePub etc., for instance with Calibre.
If you are interested you find the details, a sample (converted to HTML), and the conversion tool (for the Windows command line) here:
www.dunyazad-library.net/plaintext.htm
Thank you for any comments, suggestions, questions etc.!