Author Leah Dieterich is really good about writing thank-you notes. And not just to people who send her birthday presents or host her for a weekend. Since 2009, Leah has written a thank-you note every day to objects, ideas, places, or people. She's given thanks to clean sheets, men who walk Pomeranians, and her own laziness. At first she kept them in a box, but soon she started a blog so she could share her gratitude. Last month, she published a book, ThxThxThx, of these letters, as well as some she saved for her offline readers.