Not exactly books, but I keep files and files and files of collections like tiles, architects, rooms I like, lighting, garden, equipment, textiles for the fantasy home I’ll likely never get to build. I just had an epiphany. My mother had a room in our house with a big old typewriter surrounded by files and files of things she liked. OMG.
I’m my mom.
Then there are the files and files of places to travel that I’ll very likely never visit. Broken down by state, region, continent, country. OK, it appears I spent those years at art school to become a scrapbooker (not that there’s anything wrong with that!)
When I was doing graphics I kept clip files of everything. What if someone would asked me to draw a tiger for a job? I had files on animals (mammals, birds, fish), transportation (boats, trains), flowers, trees, you name it. I was prepared to draw anything.