I might be completely out of tune here but ever since I wrote about the g-pod-acceleratorthing last year there's been a little thing oin the back of my mind and the discussion with WincenT and Canadien on firmwarewishes and requests
brought it back to attention.
The cadencething with bikes, that counts your pedalling, how sensitive are they to distance? 5cm? 15cm? 50 cm?
I assume you have a sensor on the bike and a little thing on your pedal... if that little thing is moved to your foot and the sensor is placed somewhere, could it work as a lapmaker? i assume not since the short time there is when you pass it won't be enough for the sensor to communicate with the watch even if the sensor and the pedalthing would work. Then you would have to leave the watch with the sensor or wear the sensor instead of the pedalthing...