Simple, albeit buggy game made whilst on break creating another Google Maps application.
So here is the idea. A target marker is randomly generated on the map (most of the time). Your guesses are in clickable red markers. When you tire of guessing (which you surely will), just click on the target marker to find the coordinates.
In the future, making a simultaneous multiplayer version would be a worthy goal
You can play this game at: https://geomarker-roulette.firebaseapp.com/