GBA GB Maps turns a Game Boy Advance into a working satnav, a concept that was pure vaporware back at E3 2004 but is now a real cartridge.
The UK road network and 1.7 million real postcodes fit on a single 32 MB cartridge, and you can type in two postcodes to get turn-by-turn directions with distances. Map data comes from OpenStreetMap, with postcodes from the ONS Postcode Directory.
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