If you're really good at some trick and do it a zillion times in a row, chances are you could make or break a new world record. Like Army Lieutenant JaLyssa Walker, who did an incredible 49 backflips in a row down the length of a football field. She flipped far more than she needed to -- the previous record was just 35 backflips. In fact, she said she stopped only because she ran out of room at the end of the field!