One EPUB formatting question which I recently got interested in was: how to create a bilingual poetry book? That is, if you want to have a book of poetry in one language with line-by-line translation to another language (to aid a reader who knows the language of the original not too well), how do you do that? In a paper book, a good and well-tried solution is to have the texts in two languages placed on the left and the right page, facing each other. For an e-book, unfortunately, that approach cannot be reused; in particular because with an e-book you usually have only one page visible at a time. Splitting the page into two columns may be acceptable for short citations, but to format a whole poetic collection in this way would be inconvenient, for the columns are somewhat too narrow in this case even on bigger devices.