Notable appearance: Batman #611
When Poison Ivy has Superman under her control, she orders him to attack Batman and Catwoman during Jeph Loeb’s best-selling storyline, “Hush.” The Man of Steel’s initial attack sends both Catwoman and the Dark Knight into the water below with very little hope for survival. Fortunately for a quickly-drowning Catwoman, not only can Batman swim, but he has miniature propellers built into his boots that allow him to glide through the water.
Within moments, the Caped Crusader grabs Catwoman by the hand and brings her to safety. Like most of his gadgets, we have never seen these propellers before or since their one appearance, but they’re very cool nonetheless.