Tumbler, the name of the Batmobile, is said to have been named by the original author Frank Miller himself.

A total of 5 Batmobiles were actually produced for the film, and all of them were used for filming.

batman-begins

While filming in Chicago, an unlicensed drunk citizen’s car crashed into a Batmobile. He said he saw the Batmobile and mistook it for an alien spaceship, thinking that it had invaded the Earth.

Source: daum