If you lock your keys in the car and the spare keys are at home, call someone on your (or someone else’s) cell phone.
Hold your cell phone about a foot from your car door and have the other person at your home press the unlock button of your key fob (clicker), holding it near the phone on their end. Your car doors will unlock. Saves someone from having to drive your keys to you.
Distance is no object you could be hundreds of miles away, and if you can reach someone who has the other “remote” for your car, you can unlock the doors (or the trunk!).via email from John Farrell, Wed, 25 Oct 2006 07:31:09 -0700
I can’t vouch for the validity of this tip, but if it works, it could surely be useful.