All of my cars have had names.
My first car, a silver 1999 Toyota Corolla, was named Donatello. My friends and I were all doing a sort of Renaissance thing...Kitty's was named Michelangelo, Bandaid's was meant to be Raphael (except she never got a car, at least not back then), and so on. It was a great car, but unfortunately he lasted less than a year before I plowed him into the back of a Ford Mustang on the freeway.
Car #2 was a dark red 1989 Pontiac something...a Bonneville if I remember correctly. I named it Krueger, because the color reminded me of blood, and the beat-up machine just looked like it ought to have a sturdy name like Krueger. It was a car with family history - my father bought it new, sold it to his father, who sold it to his daughter, and eventually she sold it back to my dad. Apparently, she and her husband had named the car "Freddie", and although I didn't know this 'til long after I'd named it, it seemed to really validate my name choice.
After Krueger's engine died spectacularly on the freeway in a burst of smoke and flame, I started driving Mercutio, a silver-blue Honda Camry from the mid-1990s. It was a used car my dad had bought for my brother, but since he wasn't driving yet and I needed wheels, I used it for a while. I really can't remember how long I drove that car, but I doubt it was longer than a year at most. The car was eventually returned to my brother, who drove it until it was practically falling apart, at which point he sold it to my boyfriend.
That was a series of three cars in less than three years. Eep. That's awkward.
In August 2005 I bought my current ride, a silver Civic. I was excited because it was the first major purchase I made in my own name. It's been good to me; no major problems in the past six years. I named it Amadeus, which suits him well, although I'm now sad that I can't use Amadeus for a child.
I really couldn't tell anyone why I use Italian names for my Japanese-manufactured cars, except that it seems to suit them.