One of the main purposes of registration is for recovery of stolen bikes (Arlington offers free bicycle registration and nationally there are many free bike registries). Ohio State has a pretty interesting take on it though.
Use the latest technology to "Bug Your Bike" with a free RFID (radio frequency identification device) as part of Student Affairs Risk Assessment efforts to prevent theft.
RFID could make recovery much easier
To date, Ohio State University's scheme has been successful in the sense that 547 cyclists have registered their cycles, recovered bicycles have been returned to their owners, and students seem to like it
Similarly there is the Bike Shepherd which uses a tag which anyone with a smartphone can scan to see if a bike is stolen or not.