All the books
I love those lists in the backs of books, you know the ones that list other books from the publisher. There is something so magical about them. They are all the books you could or should or would read, the same way Lonely Planet travel books list all the places you should go before you die. It is easy for your mind to wander off and create a future you reading or doing these things, You could read the Unberable Lightness of Being or the Bell Jar. You can picture it. On a beach or in the time you might spend studying. They are always classic, and they always inevitably make you wish you had read the, or fell like you should read them. You could be that person who has read all the classics. It is easy to create this magical, perfect, smarter, more cultured you.
Then there is the wall. There is the moment when you realize that you have enough trouble finishing the book you are already on, or that you found Sylvia Plath whiny. You are you. You are reading this book. You are not at the beach. Back to your book. Although, perhaps afterwards there will be time for some self-improvement.