I’m one of the creators of Buy Me A Coffee (Y Combinator W19), which is used by 80,000 creators to build their fan base.
Before Buy Me A Coffee, I built about a dozen software projects, but the ones that I’m really proud of are WhatRuns (2017) and AdIndigo (2010). WhatRuns is a free browser extension that allows you to look up the tech stack of any website in one click. More than 200k developers and designers use it today. AdIndigo was an ad network that I scratched together when I was 14, making it even more special to me. I used to make some money from my blogs, and figured its a good idea to launch an Adsense alternative dedicated to bloggers. Boy, was I wrong. It served up to 6 million ad impressions at its peak, but I ran out of money and advertisers in less than six months (if I recall correctly). Well, I hope I remain that naive and confident :)