When I listened to On Air - Live at the BBC Volume 2 recently, I noticed that some of the "shake"s in "The Hippy Hippy Shake" (specifically the one after the line "Do the hippy hippy shake shake with all of your might") are sung with a melisma (G E). Since the note changes, there's a musical sense of that "shak[ing]."
I think this is also present in the version on Live at the BBC, but it's more subtle.
