remember the days when the key used to have an integrated light? my dad's old BMW used to have this - obviously in those days remote locking was not a feature that had been invented yet and having the little torch helps find the keyhole. i kind of miss having the torch.
Whilst waiting for my Golf, I borrowed a couple of cars that had keys with LED's on them (an old Saab and a Smart Car!). Neither of the LED's worked!!
The other thing that everyone forgets - is that in the freezing weather, the locks froze and I had to blow hot air in for a few minutes until I could turn the key

Remote central locking... what a genius invention
