Moderately related: a blog post by Ethan Zuckerman on the architecture of serendipity. Zuckerman is talking more specifically about enginnering serendipity in media, consuming information in such a way that you have a more diverse selection, rather than only consuming what you already think will appeal to you. But the point seems similar: we should build in opportunities for serendipity, breaking up a routine that is locally optimal to enable greater gains.