It's a common question for folks in this line of work: If you had to pick just one car to drive, what would it be? Just as common an answer: The BMW M3. The car isn't perfect, but it may be as close as we'll get in this world. The last M3 was such a wonderful driving machine that it could make a grown man weep. Now in Geneva, BMW is showing us a “concept” of the next M3, based on the current 3 Series coupe and powered by a 400-plus horsepower V8. It also has a carbon fiber roof, unique aerodynamics and styling, and the potential to start a whole new round of waterworks among those who drive it.