Commodities funds that hold WTI are also scratching their heads over what to do about buying and selling an oil that no longer reflects the wider global market.

ECONOMIST: What, exactly, is the price of oil?

"We're actually just scratching the surface of what this can do for us, " he says.

NPR: Crop Cops Take to the Sky

Thanks to the lack of an effective regulator, investors are left scratching their heads, unsure of what to do when something seems wrong.

FORBES: The Shape of Things to Come (December 1, 2001)

Design a steel frame is lifted onto the build table and the team walks around it, looking at the frame from all angles, scratching their heads and imagining what they could do with it.

FORBES: Planning Innovation?

Criminologists are still scratching their heads as to why that is but they suspect it may have something to do with the global economy.

BBC: What do we value about the police?