I don’t think I would want to be part of the creation process but another Zero Escape or Somnium Files game

In no particular order:

• VR arcades
• Laser tag
• Art exhibitions

Building and running a multiplayer game on one might be cool. Websocket is nice for making simpler real-time games for the browser. Godot also has multiplayer networking support but I’ve never tried it before.

You do have to open up the Pi to the public Internet though to get any people to play. I use Tailscale Funnel but there are probably also other tunneling solutions