As summer approaches, researchers at Auburn University have performed a study demonstrating the dangers of that ubiquitous summer accessory, the flip-flop.  They recruited volunteers and recorded their gait in both sneakers and flip-flops.  In flip-flops the subjects took shorter steps and didn't raise their toes as far as they did in sneakers. This makes sense, if you think about it.  When we wear flip-flops we curl our toes down to keep the sandals from flying off our feet.  This keeps us fro...