Fun question, wiserworld! I always answer questions before reading the other answers (I can't wait to read them!).
If I were a car... I'd be a Ferrari (red, of course). I'd be the fastest, coolest car in sight--yet I'd be driving the speed limit as exactly as possible. I'd also be a Corvette Stingray hard-top (more practical financially), for the same reasons.
I'd also be a muscle car--a Mustang or Dodge Charger--with lots more power under the hood than it appears to have on the surface.
I'd also be a Toyota Corolla sedan (though I'd be the station wagon version if they still made it)--practical, compact, seats 4 (or 5, uncomfortably), does its job well, fuel efficient, easy to park, and few worries about security or vandalism when it's not parked in the garage. Longevity and low maintenance, too, even after many years and miles of use.
I'd also be the Subaru SVX, an awesome little sports car that they discontinued a few years ago. Hard top, but mostly glass and tiny windows in the two doors making drive-throughs usually impossible but getting stares from everyone due to the "Jetsons"/futuristic-like look of the glass wrapping up around the car onto the roof. All-wheel drive for traction control (unheard of in a sports car), and all the bells and whistles of its day.
If I have to pick one car only, I'm a practical person (usually) so I would be the Corolla.