Odd bit of trivia: On US Army bases, at least the one I lived on, the drivers' equivalent of standing with hand (or hat) over heart is pulling the car over. The only example I can think of is what is done every morning when the flag is raised and every evening when the flag is lowered. Pedestrians not in uniform stand with right hand or hat-in-right-hand over heart; pedestrians in uniform keep their hats on and salute; drivers pull over and keep the vehicle stationary. When I first lived on base, it was decidedly odd to get used to all this twice daily.