This is a map of the Australian state of Victoria, showing some of the locations for which cat registration data is available publicly. A bigger cat on the map means there are more real cats in that postcode; pan and zoom to explore.
You might say it's a map of cats, or a CatMap!
Take a shapefile of "postal areas" from the Australian Bureau of Statistics. Using GDAL, find the postcodes in Victoria (starting with 3), and convert to GeoJSON. Then, run through TopoJSON for fancy lossless compression, and run our own postcode-centroids.js
to generate display positions.