For serious cyclists nothing sucks more than having a bike stolen. You keep track of the serial number, engrave your name in the frame, but this only helps if the police actually recover your bike.
How about tracking the thieves instead? That’s the idea behind Spybike, a GPS tracker that can be hidden in the steer tube. It can upload the coordinates of the bike to a mobile smartphone or website in case of theft. When the device is activated a motion sensor detects any movements and sends an alert to your phone. Every 20 seconds or so the coordinates of the bike are uploaded, and when the bike stops it goes to sleep to conserve the lithium rechargeable battery.
httpv://youtu.be/dEeQCe2F_1I
It is probably a tool most people won’t ever need or want to use, but it will one you’ll be glad you have should your bike be stolen.