If you've built something that is actually collecting revenue, you're already ahead of a huge number of folks out there, and you can likely build it into something that can at the very least make you live comfortably, if not much more.
Website still needs to communicate the value more, but it is a fun project to keep improving.
Started off as an email a link to get paid with Stripe for art dealers but now has a focus on the due diligence and was well-timed with some EU money laundering regulations.
Growing revenue 150% month on month and will likely have to become my main source of income soon.
It's a Chrome extension that crawls and tests websites for SEO, speed and security best practices.