S.T.A.M.P.S. watches took the idea of the postage stamp and based a watch design on it. Like the real thing they have adhesive backs and come in huge array of designs, with interchangeables straps and faces.
They come in a 42mm by 42mm (non water-resistant) perforated case.
“Stick it on anything, anywhere you like. Remove it if you want and stick it again or wear it on your wrist, around your neck or on your pony-tail.”