5 years. (2011-2016) While working on my first startup (Sauce Labs), I made a robot that plays Angry Birds as a side/art project in the autumn of 2011. The serious part of the project is that you can use the robot for testing mobile apps and devices. I started to sell the robots (still as a side project) on Tindie when that first launched in the summer of 2012. I made a couple of thousand dollars the first few years, but basically broke even profit-wise. I got my first "big" enterprise order of robots in late 2014 and that made me start wondering if I should ramp things up. I formally incorporated (http://www.tapster.io) in May 2015 and took some seed funding (Indie.vc) to sell the robots full-time. Since incorporating, it's now veeeery close (this summer) to ramen profitable while paying a few salaries.