I might have to reorganize my library by the metaphysical attitude of the authors. I’d have poets, novelists, essayists, philosophers, businessmen, design theorists, anthropologists, artists, historians, sociologists, theologians, etc. all grouped together by philosophical like-mindedness, liberated from their inadequate categories (or maybe benevolently imprisoned by my own).
My primary consideration would not be the usability of the system, but rather, what would it be like to sit in my chair, surrounded by my books organized this way?
(Experimental pano shot of my untidied office.)
Organize them by color.
Or size. Width left to right. Height top to bottom.
Or, you could organized them by the font families used for the book title.
Or by scent. From crumbling to musty to ex-library copy to freshly minted to print-on-demand.