Base-42

Yes, well, having exhausted so many systems and themes ... A comment on Facebook stuck with me and led to this: ALL the systems. But a maximum of 42 books in each. Thus:

42 books in alpabetical-by-author. 42 books by number of words in the title. 42 books in random chaos order (they are spread out in horizontal piles all over the shelf, in character). 42 books by number of pages in book. 42 books spine-inwards. 42 books by colour.

Graphic novels staying out of the race... 42 books in chronological order: by the time (on Earth) in which they are set. 42 books alphabetical by the place in which they were printed, town or country. 42 books in numerical order by ISBN. 42 books thematically-by-title-words: place names, from rooms and buildings to worlds. 39 books (workin' on it) thematically by title-words: light/day/sun-to-shadows/night/moon/stars and similar.

40 books (workin' on it; could have filled it easily if not limiting books-per-author) on theme: wolves and werewolves. 28 books (workin' on it; recommendations welcome) featuring Marlowe, Shakespeare, Byron, Keats, Shelley. 42 books in trilogies (poetic interpretation of). Absolute Sandman staying out of the race. A handful of books in alphabetical-by-first-sentence, which is the category I'll now fill with recently-read till it reaches 42.

42 books alphabetical by author's first name. 42 books by weight. 42 books alphabetical by protagonist's name. 42 books with names for titles. 42 books alphabetical by title.

Hopefully the images should be clickable if you want to look closer on titles...