Anyone have a link to a collection of useful topojson maps (the format that can be used in the Shape Map Visual)? I've found tools that will let you create these, and I've even found a US map that contains counties but no useful ID.
Surely someone has a collection of common maps already in topojson format. I'm looking right now for US zip codes, US counties (perhaps ID'd by FIPS), and US congressional districts.
Thanks!