In no particular order:
- Arlington Parking Availability - check the status of on-street parking near your destination in Arlington's Metro Corridors based on real-time data from the Performance Parking Pilot.
- dcbikemap.com - an online regional bike map for the DC area using open GIS data from local jurisdictions
- parkingdirty.com - a project to crowdsource data on blocked bike lanes in Arlington based on snapshots from the County's own traffic cameras.