>>>From BBC News: "The aquifer is said to hold some 200bn cubic litres of water." My brother wondered what a square litre would look like.
>>
>>Very shallow :-}
>
>Yeah that metric stuff is silly. Give it to me in square gallons.

Nah, more useful would be hectare-foot or acre-metre
(a partially "metricized" version of acre-foot ( http://en.wikipedia.org/wiki/Acre-foot ) )