https://FreeSolitaire.win brings around $500/mo in advertising revenue. It’s a Klondike Solitaire PWA (progressive web application). I started making it in 2016 and I’ve been slowly iterating on it over time. It has stayed minimal & lightweight, on purpose. No framework, no cruft, no obtrusive ads. Fun fact: because it’s so lightweight, it was included in 2020 in Moya ( https://play.google.com/store/apps/details?id=nu.bi.moya ), a popular messaging app in South Africa that is “data-free” for users (it does reverse-billing). Now ~40% of players are South Africans! Discussed on HN from to time, for instance: — https://news.ycombinator.com/item?id=42026575 (38 days ago, 19 points) — https://news.ycombinator.com/item?id=41971887 (43 days ago, 25 points) “Quick side-note. Thank you for freesolitaire.win. It's such a beautiful implementation of solitaire. Works so well as a PWA, I can enjoy it even without proper internet connection, it's simple, does the basics, but does it perfectly. There's nothing to add to it, but more importantly... nothing to take out.” (!) — https://news.ycombinator.com/item?id=34483398 (2023, 4 points) Feedback always welcome, and happy to answer any question!