Bookshelf Sustainability

A few days before my vacation Toronto, I went through the library of books in my apartment, and organized them into two shelves, one for the books I've read and another for the books I haven't read. My situation isn't as bad as Ealasaid's, with a bookshelf of unread books that at least doubles the size of mine, but at least until I read them all, a new rule: for every book that I buy, regardless of whether I've read that newly bought book or not, I will give away one book. No rules around size or whether I've already read it, or who gets it (a friend, a stranger, the used bookstore, or the library). This is just my way of keeping the number of things in my apartment to a minimum, and ensuring bookshelf sustainability, while at the same time knowing that I'll never have to worry about running out of things to read.