Bike-mounted sensor could boost the mapping of safe cycling routes
newatlas.com
Studies have shown that many people don't commute by bike due mainly to a fear of being hit by cars. A new bike-mounted proximity sensor has been designed to help such folks, by objectively telling them which streets are the safest for cyclists.

Took me a sec to see the vision, but after reading I agree it could be a really useful idea.

Combining this with accelerometer data (road quality) and sound could make for a pretty good scoring system.