Which Airports are also Filetypes? - this map only displays airports whose three letter codes are also file extensions.
https://googlemapsmania.blogspot.com/2024/10/which-airports-are-also-filetypes.html

OpenPlacesMap - anybody can edit any place-name label in this map.
(I think I can predict where this one is going to go)
https://googlemapsmania.blogspot.com/2024/10/open-places-map.html

Guess Thy Neighbor - Neighborle is a new daily map challenge. Each day you have to name all the countries which border that day's highlighted country.
https://googlemapsmania.blogspot.com/2023/10/guess-thy-neighbor.html

GeoClash - like GeoGuessr but built on Leaflet & Mapillary. https://googlemapsmania.blogspot.com/2023/08/geoclash.html

Street name orientation in Miami. All 'Streets' are colored green and all 'Avenues' are colored yellow. https://googlemapsmania.blogspot.com/2023/08/30-second-data-viz-with-osm-gpt.html

The Overture Maps Foundation has announced its first release of open map data. It contains four themes:

Places
Buildings
Transportation
Administrative Boundaries

https://googlemapsmania.blogspot.com/2023/07/new-worldwide-open-map-data.html