I'd always heard it prefaced with:

"We don't know nobody who don't want no nine-inch nails,
We don't know nobody who don't want no nine-inch nails,
We knows the king and we knows the queen and we knows the prince of wales,
But we don't know nobody who don't want no nine-inch nails!"

Just say it and you'll find you're singing it, there's not much of a tune.