£5 voucher

My wife thinks I spend too much there, but last week I stopped at the bookshop after running a few errands because I thought I deserved a treat for having done something tedious. I only bought two books, but with the other ones I bought this year, it was enough to earn me a new £5 voucher. My third one this year, if I'm not mistaken. Now I need to find a book to spend it on. Feel free to give me your suggestions in the comments.