My wife likes naming cars and every once in a while asked me what the Mustangs name was. The answer was always "Mustang". Then my daughter got in on it and started bugging me to give it a name while we were in the car. I told her to ask the car what it's name is. She did and the response she got was a WOT second gear pull from around 4000 RPM to the rev limiter. Unphased, she uttered "the car says it's name is Berrrrrrrrrrrrrt" and "Bert" has stuck.
I did give one car a name myself. My blue '07 Legacy GT wagon is "Blubaru" because "The Subaru" was already taken by a nearly identical looking black '08 Outback XT.