EVA Foam is a great material for constructing costumes and props of all different kinds, from period armor and swords to slick futuristic robots. It is especially beloved by cosplayers and prop makes because it is lightweight, cheap, and can easily be cut
update: I tried with all my songs and yes I know it doesn't work with every song. I just think it works if you play the song on time or it works with some sort of upbeat song. But yea, it doesn't work perfectly like you would expect.