Do you use signal lights when backing out of a driveway?

I do, but my kids tell me I'm wrong. I think it lets others see that I am backing out and turning in that direction as indicated.

Added: There is no specific law againstit that I am aware of - however your back-up lights should serve the same warning purpose to oncoming traffic. Don't let the fact that you have your flashers operating lull you into a false sense of security. It is always incumbent on the driver of the backing vehicle to yield to any oncoming or conflicting traffic.