http://pledgeqanda.com/etiquette_questions_on_the_pledge_of_allegiance.php
At one time, some people would begin the pledge with their hands over their hearts, but would extend their right hand towards the flag (palm up) at the words 'to the flag'. Their arms would remain extended for the remainder of the pledge.
During WWII, this practice was abandoned, as it was so similar to the salute that Nazis rendered to Hitler.