My siblings and I were always threatened with pulling the car over.
I don't remember an occasion that this actually happened, but the fear of being spanked within an inch of my life, in front of traffic, was a powerful tool.
I don't think my mom would've actually done it, but we could get pretty loud in the backseat. Ahh, kids. This is why I have yet to reproduce.
That and the lack of mate thing. And stuff. Anyway.