Then there was the couple who were browsing in a junk shop, the husband was attracted to a pile of old musical instruments. He picked up a silver metal object and put it in his mouth and managed a couple of twangs. His wife came over and said: "What are you doing?""I've found a silver jaws harp." he said.
"You fool, that's a cheese slicer." she replied, dragging him away.
RtS (I've been waiting for an opportunity to work that one in! Wasn't worth the wait was it ?)