LeafletJS (component) can work on OpenStreetMap (data/map).
Have a look at William Charlton’s work on/with hexagonal geographical maps. Seem to be overlays for Google Maps. Scale of Hexes, Cape Town Hexagons, 12 Cities, EFHex Crestone, EFHex Knokke-Aan-Zee, Hexagons, ISEA Grid Resolution 0, ISEA Aperture 3 Hexagon (ISEA3H) DGG.
Additional links collected/contributed by William: Spatial Hexagons, Hexbinning in Whitebox GAT, Create A 3D Hexagon Grid Layout with CSS3, Tiling contiguous polygons in Google Maps, UK Hex Tile Map, British Geological Survey: GeoSure 5km hex grid, Election hex mapping, Binning data into a hexagonal grid in Google Maps, How can I make a Google Maps API v3 hexagon tiled map, preferably coordinate-based?, Example E-Shapes, Open Geospatial Consortium announces a new standard that improves the way information is referenced to the earth, Discrete Global Grid Systems, Hex Binning Land Registry Data, Election 2015 interactive, Dr. Jonathan Reades.
10+ years ago, I used this little rendering component HELIO World for PHP that was able to plot the outlines of the countries of the world (white background, gray borders). Can take a list of countries (probably by ISO-country code) to fill/highlight with color. Didn’t support a better resolution than country, but is at least a very cheap, easy option. Support for selecting/clicking countries via automatically generated image maps, custom viewport + a few more features. Web 1.0 technology, probably using GD for rendering. Package seems to be terribly outdated/abandoned.
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