BOOKS! Especially a used bookstore. The smell is just as exciting as a store full of new books. I want to touch every book. Caress each cover, every page. Kiss each word and hold them all close to my breast like a mother about to feed her baby.
I'm tired of seeing silly head canons about muggle borns bringing tech to Hogwarts and all that ridiculous stuff when there's a reason Jo hadn't implemented it. I feel like this is a good explanation for why.