What does this bumper sticker mean?

Factual Questions
1

“I drive like a cullen”. Actually it might have said "Warning - I drive like a cullen. "
Online dictionaries get me nowhere. ???

There wasn’t anything else on the car to give any context or idea, except the mandatory local soccer league decal.

2

A Google search indicates it has something to do with the book/movie Twilight.

Here’s a partial answer: http://wiki.answers.com/Q/What_does_drive_like_a_cullen_mean

3

Well, pshaw. I should have thought to type in the phrase. Thanks!

4

De nada!