For those who don’t want to retire their sketchbooks when they fill up, there’s the option of the Endless Notebook ($7 to $15). By grouping together a special pocket on the front cover of each individual notebook, it’s easy to combine different types of paper (graph, lined, blank,etc.) or to simply add on to an existing sketch book, retiring only one of the used volumes. The Endless Notebooks are composed of chlorine-free, post-consumer recycled paper and produced in the USA using 100% renewable energy.