I though this was just a concept for the moment, but the Climbing UP suitcase designed by Woo Moonhyung makes dragging your suitcase around much easier. Especially on uneven surfaces or up stairs. Most suitcases use just a single set of wheels on the bottom, but not the Climbing UP suitcase. Instead, it has rubber belt tracks like a tank, along the length of its body. It just adds that extra little nudge to help you get a bit of a break. (Link)