I didn't build one from scratch, but I recently purchased https://introcave.com for low 6 figures. Though my background is more full stack, my current day job is mostly front end. Most of the product/ux/ui work is done before things hit my desk (agency work), so I really enjoy being able to run something on the side where I'm making those decisions.

It's profitable month-to-month, but until it recoups the purchase price I'm thinking of it as a really expensive hobby. I recently purchased a better domain (https://intromaker.com), and at some point in the future I'm planning to build a more dynamic render engine and do some sort of subscription service (less targeted at youtubers and more geared towards agencies).