Check out how to set up the Makey Makey here.
Use the Makey Makey to create a musical dance mat. Instructions here for the basic dance mat. The easiest way to add the music is with the Makey Makey piano.
Feeling adventurous? Try this dancemat Makey Makey and Scratch combo. You may even be able to work it in with this fabulous Scratch game:
Not feeling challenged enough? Whip up your own MakeyMakey creation.