Ecuador has also proposed that OPEC levy a carbon tax at the oil wellhead, a concept devised by environmental economist Herman Daly.

UNESCO: World Water Assessment Programme (WWAP)

Professor PAUL KEMP (Coastal, Energy, and Environmental Resources Institute, Louisiana University): So, about 60 percent of this levy is severely damaged, and it's about, its reach is about ten miles long.

NPR: Cost of Levee Repairs Rises in New Orleans

But in addition to a flat per-gallon charge, a majority of states levy other taxes, including state, county or local sales taxes, plus various environmental and other charges.

FORBES: State Gas Tax Guzzlers

Levy wrote a lengthy article in the New York Times about how Russian security services arrested members of an environmental group under the pretense that they were using pirated Microsoft software.

FORBES: Shamed Twice, Microsoft Takes Action To Protect Dissidents