In the case of bitcoin, a strong case can be made that, even with secondary markets, certain virtual currencies lack the legal elements of material value and property.

FORBES: WinPoker Becomes First Major Gambling Operator To Adopt Bitcoin

"It shines a light onto previously hidden relationships, uncovering anomalies between such elements as bank interest, property income and lifestyle indicators before homing in on unexplained inconsistencies, " an HMRC spokesman said.

BBC: Tax form

Leases normally give the energy producers the right to build pipelines across property, or set up storage facilities, with these elements being negotiated separately.

FORBES: Shale Leases: Promised Land

The fall of Chowchilla had typically Californian elements, including a huge housing collapse that reduced property tax revenues and the recession.

FORBES: Sliding Into The Pacific? Another California City Chokes On Its Bonds