SpringVia Gizmodo...

You can't help but have noticed this shoe looks a bit odd in the heel department. That's because these 'Strutz' have a shock-absorbtion mechanism via spring-loaded heels. This, theoretically, should make shoe-induced pain a thing of the past. But do they work? Well we've not tried them, nor are we convinced about the aesthetic appeal...but they are trying. These 'Chameleon' shoes ($169) are the closest you'll get to customisation, as no two pairs are alike.