A bit off topic, but I am major fan of single developer apps and services. They generally have a focus and lack of bloat that makes them invaluable as tools to

A bit off topic, but I am major fan of single developer apps and services. They generally have a focus and lack of bloat that makes them invaluable as tools to just get things done, and because of the small business footprint they don't need to endlessly scale into oblivion to satisfy shareholders / staff wages etc. Off the top of my head I am thinking of things I use regularly like pinboard, mailmate, Name Mangler, manager.io. Even builtwith.com is (or was for a long long time) one person!