Some four years ago, I started Bingo Card Creator, a business which sells software to teachers. At the time, my big goal for the future was eventually making perhaps $200 a month, so that I could buy more video games without feeling guilty about it. The business has been successful beyond my wildest expectations and has made it possible to quit my day job at the end of this month. The amount of time I’ve spent on it has fluctuated: the peak was the week I launched (50 hours in 8 days), a very busy week in the last few years spiked up to as many as 20 hours, and the average over the period is (to my best estimate) about 5 hours.