When a competent publisher finally shows up on the ebook scene, many years from now, and puts into ebooks all the useful things authors and publishers have put into paper books over the last thousand years (concordances, indices, tables of contents-figures- tables, references, etc.) I'd be very happy to have you innovate still further and include some yet-to-be-determined-thing.
I'm not holding my breath.
Regards,
Jack Tingle