I built a distraction free writing app in 2012 to help me write, and it has been the single greatest distraction of all. it was successful, becoming the number one writing app on Windows store for years. I now have thousands of users, and it makes a tiny bit of money each month, and supporting and fixing bugs takes up most of my spare time. I have to date not managed to finish more than a sketchy first draft of a novel using the software I wrote to help me write.