Tip - Basic Etiquette for Working in a Coffee Shop

Social site Mashable brings up a good etiquette topic: Working in coffee shops without being annoying. Whether you're just checking emails quickly, using it as an office to work on your time-travel screenplay, or somewhere in-between, there are not real written rules to guide your behavior. So what should you do to use their facilities guilt-free?
Tags: Etiquette, Coffee shop, Starbucks, working, Top, Lifehacker