There's an interesting thing you can do with your feet and a tune in mind. That is to tap it out with your feet, using the heels and the toe area.
Your mind definitely goes along with it, with the heel being especially a bass note and the toe treble, melody notes.
I'm doing the famous old song "Baby Elephant Walk" right now. You know how it goes. I'll do the first part, slowly: Left heel, right heel, left heel, right toe, left toe, right heel, left heel, left heel, left toe, right toe. I don't think that's right. It's easier to do by instinct than it is to try and chart it out. Plus I have very little musical talent.
No one else can tell what song you're doing. Just you.