Most people see freelancing as pure active work, where you only earn when you are actively doing something for a client. But some freelancers have figured out ways to earn money even when they are not working, like selling digital templates, writing guides, or licensing their past work. It sounds like a good idea in theory, but it is not clear how realistic it is for every type of freelancer. Have you found a way to build any passive income around your freelancing, and how did you start?