Stock Market Game
https://stocks.tylermumford.com
I learned about the "stock market game" from my brother-in-law during the pandemic. We originally played it with the help of a spreadsheet, and it was a lot of fun. I decided to make a dedicated web app for playing the game.
(It's not really about the stock market, but "stock market game" is what we've always called it.)
It's a single page app with no backend, so it's just about tracking game state in memory. It's intended to be played either in person, or over something like Zoom—one player can share their screen so everyone can see the game and the scores.
It's proven itself to be fun, and I've shared it with other family members.