The lowly side project—you know that thing you do for fun when you have some downtime? The history of the Internet is rife with stories of side projects starting as innocent little ways to kill some time or scratch an itch only to turn into something much larger. From Blogger to Flickr to Twitter to Slack, a lot of very popular services started out as small side projects before eclipsing the very thing they grew from. And they’re not just important for startups, they’re also vital to anyone working on the web today. Thanks to a plethora of self-directed learning sites, there’s not much stopping you from building anything you can dream as your next side project. In the end, they’re great ways for anyone to expand their skill set, build on their hobbies, and impress future employers. It’s time for side projects to take center stage. . . . . . . . . . . . . . . . . . . . . . Matt Haughey is a veteran of the Internet, starting from the first days of blogging when he created MetaFilter and later with his work on Blogger. He helped launch and design Creative Commons and most recently has helped Slack share their vision for making everyone's working lives simpler, more pleasant, and more productive.