Just to chime in with a travel tip: please don't turn off your phone or turn the ringer off. We often have people who think they've lost their cell phones at the checkpoint. A solution I use is to call their phone from the checkpoint. Nine times out of ten, they can either hear the phone or feel it vibrate in their carry-on. Other times, we've heard the phone ring from a bin on the conveyor belt or at one of the screening tables. I've also had it when the rental car agent, where the passenger dropped off a rental car, answer the phone.

Best travel tip of all: put your cell phone inside your carry-on rather than placing it separately in a bin. People rarely forget to take their carry-on but will forget to pick up any loose items placed in one of the bins or small bowls.