Think about a shelf full of modern bookcovers with bright colors and various competing fonts. A rainbow of dust jacket colors sometimes tamed by grouping. What feeling does that create in comparison to a shelf full of vintage books? Brown, navy, muted red or soft green. The titles, sometimes barely visible with a slightly gold shimmer. Even the dust jackets' colors are muted by time and don't scream for attention.
I've picked up quite a few books in the last two weeks (about twice what is pictured below). I also have gathered a great collection of vintage craft books and nature guides.
If you are a crafter, vintage books are a wonderful resource and great as supply as well. A few items from Etsy crafters for inspiration:
From Memory Dust on Etsy
By ShannonKayeDesigns on Etsy
Second hand books are affordable as decor, as reading material, or art supply. Check the shelves at the antique, consignment, or thrift stores and find some treasures. P.S. - There are plenty of current titles as well!
I'll be listing vintage books occasionally in my Etsy shop. I've gotten lucky and even found quite a few first edition copies.