I built a route planner. I walk around the city where I live a lot and love exploring new streets, but at some point it became difficult to plan routes through streets I hadn’t walked down yet, so I created an app that lets you plan different types of routes. You can specify the percentage of overlap with streets you’ve already traveled, create a route from point A to point B, a circular route, or a one-way route. You can add streets to your favorites or exclude them. The app runs only on my local computer. I use it all the time.