Fascinating idea from Toyota. A watch that acts as a key. RFID, probably.
Toyota is working on a new handy gadget to go with their line of Crown cars. They are working in conjunction with Citizen to develop a watch that transmits a radio signal to the car once the hand gets close enough. Basically, you grab the door handle and the door unlocks. They also plan on implementing manual buttons on the watch similar to how keyless entry units work now. Expect to see this hitting Japan first in the coming weeks.
Check it out here.