As the 1990s shifted into the new millennium, tattoos and piercings went mainstream and the rise of the internet began. BMW also gave the world the 4th generation, and to many, the definitive 3 Series. It was curvier, sleeker, and came with one of our favorite straight-6 engines in 320i and 320ci models and up. The sedan came first, followed by the coupe, convertible, touring, and compact models. The E46 sold 3,266,885 units in total and is, to this day, the best selling BMW model ever.