keyless start and drive

you could wire the car to a universal transponder interface ....and carry the transponder.  when you pass the transponder near the ring...the ign will turn on.  if this is what you want ill find the parts for you.

   XS

You'll need a transponder system with a pretty good range on it!  xscash have you seen any with ~3 ft range?  It would be cool to install the sensor under the drivers seat or something.

Nissan uses multiple antennas though, one in each door, and one under the dash if I remember right.  I was looking though the M45 service manual, its got a TON of information on the system.  Pretty cool stuff.