Compared to coal, which generates almost half the electricity in the United States, natural gas is indeed a cleaner, less polluting fuel. But compared to, say, solar, it's filthy. And of course there is nothing renewable about natural gas.

When it comes to global warming, coal is the gorilla in the room.

In the U.S. alone, weather disasters caused $50 billion in economic damages in 2010.

If you think Wall Street firms have it good, you haven't looked closely at Big Oil.

Extracting oil from the tar sands is a nasty, polluting, energy-intensive business.

Mark Ruffalo, aka the Incredible Hulk, is the natural gas industry's worst nightmare: a serious, committed activist who is determined to use his star power as a superhero in the hottest movie of the moment to draw attention the environmental and public health risks of fracking.

In the Arctic, things are already getting freaky. Temperatures have warmed three times faster than the global average.