Anonymously: create a `.somewhere` file in your home dir with
Publicly: create a `.here` file in your home dir with
Every 15 minutes this program runs `who --ips` and then looks up IP geo info on opted-in, logged in users. It hits Google's geocode API with the "[Region], [Country]" data it found to get general coordinates, and generates this data, stripping out usernames for anonymous users. When viewing the map, an AJAJ request is made to get the data and the points are added to the map.
You can see for yourself in the GitHub project, where contributions are welcome!