The Levitating Superconductor Speakers by James Coleman has got to be one of the coolest I’ve seen! The concept works by housing a superconducting element inside a transducer, which can be suspended in a superdiamagnetic field by an electromagnet. Changing the electromagnetic field strength will cause the transducer to oscillate, which will impart sound directly into the air. Crossing my fingers that superconducting technology advances quickly because I want both the black/gold and blue/silver versions!
Designer: James Coleman