Oil

Apparently, a lot of the hubbub in Iran has to do with Iran wanting to sell Oil in Euro, rather than the norm of dollar. A more indepth article can be found here.

For some reason this makes me thing of L. Asimov and predictive mathematics...

Peak Oil is also called "Hubbert's Peak," named for the Shell geologist Dr. Marion King Hubbert. In 1956, Hubbert accurately predicted that US domestic oil production would peak in 1970. He also predicted global production would peak in 1995, which it would have had the politically created oil shocks of the 1970s not delayed the peak for about 10-15 years.
(stolen from here)