You know, the part in Big when Tom Hanks plays the very same gigantic piano in FAO Schwartz? (This was the only video I could find of the original, it's a recording of a tv. But honestly if you haven't seen the movie, you have no business watching this, just go rent (or buy, it's probably super cheap these days, I think I saw it in the $5 bin at Wal-Mart) it.
Figured I'd include this while I was strolling down my random things marginally related to childhood favorite movies. But still, these girls totally beast it.