a very cool example. I don't know if this has been here before but...
[video]http://mashable.com/2014/01/02/acoustic-levitation-video/#:eyJzIjoiZiIsImkiOiJfN2Jpc212OTh4ZXd2bjhoMiJ9[/video]
[video]http://mashable.com/2014/01/02/acoustic-levitation-video/#:eyJzIjoiZiIsImkiOiJfN2Jpc212OTh4ZXd2bjhoMiJ9[/video]