San Francisco (Fortune) -- Eco-consciousness appears to be hitting the mainstream. For years, it was only the truly committed, the painfully hip and the guiltily ashamed who were willing to stand up in public and say they were willing to do something for the environment.

Now environmentalism has gone way beyond the sandal-ista crowd. We just may be entering a time when everyone from average individuals to giant corporations to politicians of all ideologies agree that the evidence of environmental degradation is so overwhelming that it's finally time to act.

A couple weeks ago I listed some examples of how corporate America was getting into the act, from Wal-Mart pushing its massive employee base to use energy efficient lighbulbs to Weyerhaeuser's decision to burn more biomass and less fossil fuel in its paper mills.

Judging from the conversations on panels and in hallways at Fortune's Brainstorm conference in Aspen, Colo. just before the July 4th holiday, the conversation is picking up steam.

Carbon neutrality is going to be the next big thing. Movie star Al Gore had promised to personally become carbon neutral and he is urging others to follow his lead.

How to be carbon neutral, though? It turns out it's as easy as writing a check. Various organizations will take your money and then go invest in planting trees, developing wind farms and other activities that "offset" the carbon dioxide you're responsible for creating.

It sounds a little nutty, and there is disagreement as to how well such a system works. But if you think about it, it's kind of a cool idea. Not all of us are cut out for driving Priuses, carrying burlap sacks to the market or putting on a sweater in our cold living rooms.

If not, fine. Paying someone else to do the things you're not willing to may be incredibly bourgeois, but it is in fact good for the environment.

There are a million small ideas out there for helping the environment. Panelists at a Brainstorm session on global warming had a few of their own.

Lawrence Bender, producer of Al Gore's film, "An Inconvenient Truth," told of the big corporation that is getting its truckers to turn off the air conditioning when they are idling.

Carol Browner, former administrator of the EPA, advocates national legislation to reduce carbon emissions that would replace a patchwork of local regulations that dog businesses around the country.

John Hickenlooper, the mayor of Denver, points out that tiny efforts, like educating people to keep the tires on their cars filled, will contribute to better gas mileage and lower emissions.

Fred Krupp, chief of Environmental Defense, wants to see a federal carbon cap along with a system that would allow companies to trade credits toward achieving that cap. (Sens. John McCain and Joe Lieberman have proposed such legislation that so far hasn't gone anywhere.)

This is an issue that is anything but neat and tidy; even people who call themselves environmentalists aren't in lockstep. Venture capitalist Vinod Khosla, for example, is a big proponent of forward-thinking ethanol technology. Lester Brown, a noted environmentalist, would far prefer to see the country focusing on wind power. They clashed in Aspen.

The point isn't the disagreements, however. The point is how much activity is coalescing around the need to do something to ensure the planet's future.

Have you joined the mainstream on this issue yet?

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