Code
In no particular order
Map Warper
OpenStreetMap iD editor
openstreetmap-website
OpenStreetMap CGImap
makesense.ai
3dmr
Data
NYC Open Data:
New York City streets, building footprints, metadata
OpenStreetMap:
Georeferencing base layer for rǝ warpǝr; road and street data
NYPL Digital Collections:
Scans of fire insurance maps, maps metadata
Open Data DC:
Historic Data on DC Buildings
Microsoft:
US, Canada, Australia, Uganda, Tanzania building footprints
NYC DoITT:
3D models
Adamlink:
Amsterdam historic buildings footprints and metadata
Paris Urbanism Agency (Apur) Open Data:
Paris and Greater Paris building footprints
Los Angeles County Open Data:
Los Angeles County building footprints
City of Chicago:
Chicago building footprints
OpenDataPhilly:
Philadelphia building footprints