The symptoms the vibrating palm produces are simply that the sufferer will go to a shop and buy a hat that doesn't suit them.
Coined by the awesomest show ever, The Mighty Boosh.
Vince Noir - "What's that? That was nothing."
Howard Moon - "Feels like nothing, but that's the vibrating palm. You feel alright now, but two hours from now, you go to a shop, you buy a hat, it won't suit you, Oww!! Chika-chika!!"