Fiddlestick

The fiddlestick can produce different sounds depending on how it is used.

"He thought the missing pen was just a fiddlestick, until he realized it was his lucky pen."

"She considered the issue to be a fiddlestick and didn't give it much thought."

"Uh, let me think, fiddlestick, what was the name of that movie again?"

"The old-fashioned way of starting a fire involved using a fiddlestick to create friction between two pieces of wood."