If you work in an office it's likely you've received the same email as me once in a while. It's the person who asks you to do some small task and once you email them with the information they've asked for they reply to you with this one-word email: "Thanks!" I'm on the fence about these emails. Sure, they're nice, but they break my stride when I stop whatever I'm doing (looking at new bikes online) and it takes a while to get back to work. I read a long time ago that email and IM is bad for business since on average it takes people 15 minutes to get back to their pre-interruption productivity levels. I suppose that assumes you were being productive when the interruption arrived. Added up, these thank-you emails cost more hours of work than putting a foosball table in every office cubicle. And I would get behind an office-wide ban on one-word emails if it meant more foosball.